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Posted: 3/31/2005 6:28:14 PM EDT
Link Posted: 3/31/2005 6:45:13 PM EDT
[#1]
Link Posted: 4/21/2005 12:24:59 PM EDT
[#2]
The FAQ, ver 1.2.  Updated to add information about NFA/SBR options and to clarify and update information about gas system configurations.

The FAQ:

* Why is it called .221/300, .221 TIW, 30/.221, 300 Fireball, or whatever? I thought that it was called the 300 Whisper? Are we talking about the same thing here and are they compatible?
 JD Jones, of SSK, is the original inventor of the 300 Whisper. I’m sure that there have been many wildcatters over the years who have necked up and down the .221 Remington Fireball, but it was JD who put it all down on paper for the AR and put a name to it. Check out his web pages for the full story. He standardized it, promoted it, fully developed it, published it, and still sells it. He’s the man.
 That being said, all variants are based on the same .221 Remington Fireball case, and all of them use the .221 Fireball headspace gauges for go/no go. Namely, 23 degree shoulder and 1.400 brass OAL, with a 2.250 Max COAL based on the .222/.223 Remington case head family.
 There are minor changes from one to the other to keep them from infringing on each other’s rights. There will be a slight difference in throat diameter, throat length, neck length, neck diameter, and a variety of others mostly non-critical dimensions.
This is why it is so important that you know what you are getting. If you are having one made, ask your gunsmith for a chamber reamer print, and LISTEN TO WHAT HE TELLS YOU TO DO.
 If you are buying one second hand, or from a retailer that does not know the heritage of it, try to contact the original manufacturer.
 Last resort is to have a local smith, or you if you are so inclined, make a chamber cast using Cerosafe (available from Brownells) and WRITE DOWN the information in your logbook for safekeeping.

* What is the optimum barrel twist for my Whisper?
 Because the eventual use of just about every Whisper is subsonic and suppressors, this is pretty cut and dried. Referencing any ballistics program, we can see that the 200-240gn 30 caliber bullets will not reliably stabilize at 1050-1100 fps (sonic) in anything slower than a 1/8-twist tube. There are a lot of 1/10 twist barrels out there in Whisper, but they usually will not shoot anything heavier than a 175gn bullet subsonic reliably. With supersonic rounds, it does not matter much.

* What is the best length of gas system to use?
 Carbine has proven to be the most useful overall, due to the universal availability of set up and parts. Nothing new to learn about the carbine set up after 30+ years.
 That being said, there are several custom builders who have figured out the what works with the most common components/loads using a pistol length system and a properly sized gas port.  These bear looking into if you and/or your gunsmith together decide that the flexibility of an adjustable system is not really what you are looking for.
 A review of some basic principles of the AR, if you are not familiar with them. To get an AR to cycle, you need enough dwell time with the bullet in the barrel AFTER it passes the gas port to allow a sufficient quantity of gas to reliably cycle the gun to work it's way through the gas tube. Too short of a barrel AFTER the gas port and you're going to have real problems, a la the Commando variant of the AR and the various SBR and pistol variants, they're all hard to get to cycle reliably with known full power ammo, much less the variable of hand load sub sonics! This is also part of why the gas port was located further back in the M1A(M14) when it was retooled off of the M1 Garand, to allow a longer dwell time at a more reliable pressure and to allow for variances in powder burn rates. (The Garand is notorious for not liking anything but a very narrow selection of military loads). Likewise Dissipater configurations of the .223 AR that are made from a cut down 20 inch barrel require gas port tuning where the 16 inch carbine systems do not.
 The size of the gas port, as well as it’s location, on the barrel play an integral role in determining how much gas gets to the bolt carrier and when it arrives in the firing cycle (dwell and timing).

* I know that JD Jones uses a proprietary adjustable gas system but I'm not sure what length it is. How does he get his AR s to work?
 SSK is currently using an in house designed system that is a few inches shorter than a standard PISTOL length tube with a monolithic style of gas block/regulator.  The proprietary block which has 3 positions, H, L, and Off.   Seeing as it’s a specialized, proprietary system, it is doubtful that over the counter pistol parts could be made as reliable without some major tinkering. Remember, the stuff from SSK is high end, and the usual configuration from them is designed for the use of a dedicated suppressor.

* Some builders are using pistol length gas systems, but to me that seems like just extra pressure to beat the bolt up with. Needless to say I'm a little confused as to what the best option here is?
 I hear you. There are adjustable gas blocks, tubes, pigtails, shorty, carbine, middy, rifle, pistol, expansion chamber tubes, and a whole variety of other strange devices for getting the gas to the bolt/carrier assembly. I have found that of the various manufacturers offering Whisper variants, there is really not a bad one, with a few minor exceptions. Depending on your eventual use, you could either order a barrel and DIY or have a complete top made up. The key here is to listen to what your gunsmith tells you, in general, as all of the information here is pretty much standard fare for the Whisper and it’s variants, I have just collected it and put it in to one place for you.
 I would suggest that you stay with an adjustable carbine length for your first project for the purposes of reliability, serviceability, and availability. Once you are familiar with all of the aspects of brass making, loading, and shooting the Whisper, then you may want to branch out.  If you already have some experience with suprssers and sub sonics, or the other variants of the Whisper family, a more specialized system would probably suit your needs better.

* Is gas tube length as critical if one uses an adjustable gas block/tube?
No, not so much, within limits. The usual procedure is to open the gas port to max size, then use an adjustable gas tube or block in the carbine configuration so that you can tune for super and sub sonic loads. There has been some limited success using pistol parts, but they are usually on SBRs intended to be shot only with a specific suppressor and a specific load. The “special” configuration AR s are a “tuned system”, usually a one off specialty construction, and have limited utility overall. If this is what you want, go for it. Other than that, go with the carbine set up, it is the easiest to tune, use, and service, as well as the cheapest and quickest to produce. The adjustable carbine set up simply cannot be beat for utility in a sporting firearm.

* Olyarms has a fixed carbine gas system that sounds like it's extremely picky and understandably so based on the above information.
 A fixed system (non adjustable) will work well with a specific load and firearm/suppressor matched set. Stray any from that and you will have trouble with accuracy and reliability, but once you find that magic load, it should work forever. That being said, if you are going to invest in a dedicated, non-adjustable system, I would recommend that you go as high end as you can afford, even if this sets your timetable back. High-end systems tend to have a wider “sweet spot” due to better raw materials and tighter tolerance machine work. Also, the high end/specialty shops tend to produce one offs that are KNOWN to work with a few given combinations.
 As far as the Oly unit goes, I have personally never met one that I ever liked or got to work well reliably with both super and sub sonic loads, for a variety of reasons. Good second hand market for this item for a reason, IF you can find a buyer! Good tinker projects if you like that sort of thing. They can be fixed and made to work, usually with an adjustable block or tube installed with the reaming of the gas port to max size, and the usual tuning and tweaking by a master AR Whisper tuner/smith.

* What is the optimum barrel length for a Whisper on my AR?
 This is a tricky situation, because of the laws regulating minimum barrel length. 16 inches if you're going to go with heavy/subsonic and/or suppressed. Anything shorter will require registering a Short Barrel Rifle (SBR) on an ATF Form 1 ($200) and special tuning. There are specialty SBRs out there, and they are intended to use a dedicated, specific suppressor and load more often that not, as a matched set/system.
 With that, the Whisper barrels for the Contender are in the 12 inch range, and display amazing accuracy, with minimal muzzle blast, which seems to indicate that all the powder has been burned under pressure in the barrel.  Accurate, safe loads can be made for each specific combination.

* Is 16" the optimum "legal" length or just the optimum period? I want whatever shoots the best and I can put a permanently installed barrel extension or flash suppressor on if need be should the optimum length be less than 16".
 OK, this is where it gets very tricky with the AR, and the answer is, it depends.
As most SUB sonic loads are made with pistol powders, that's a hard question to answer a ONE optimum length. Most people shoot super and sub sonic loads, so the 16-inch becomes the de facto standard for utility as well as legal purposes UNLESS YOU ARE WILLING TO FILE THE ATF FORM 1 ($200) AND REGISTER YOUR FIREARM AS A SHORT BARRELED RIFLE.
 I would think that JD Jones would be the man to ask, as I'm sure that there's nothing that he hasn't tried on that cartridge.
 This optimum amount/pressure of gas will be different with different loads, thus the adjustable gas tube. Generally, you have SUPER and SUB sonic loads. A gun, with a given barrel length and a set gas port size, will usually operate A) Great with A SPECIFIC super or sub sonic loads (pick only one) or B) Lousy with both. Thus, SBRs are usually higher-end units intended to use a high-end suppressor for sub sonic shooting only.
 Adjustability is built into more economical sporting arms such as most of the general shooting public is likely to find useful.  Thus, for the shooter not wishing to venture into the National Firearms Act Form 1 territory, the 16 inch barrel is the only option for an AR platform, with adjustability suggested to allow for optimum tuning.
 Essentially, the 16-inch allows the optimum TUNING length, if you will, for a rifle/AR platform and the Whisper. Going any shorter and you're likely to overly affect the tune-ability and harmonic of the gun for the average shooter. Not to say that it can't be done, but accurate and reliable super and sub sonic loads are harder to get than you might think, due to the dynamics of bullet flight and AR gas system. With 16 inches of barrel to play with, an adjustable gas system in carbine length you have about the widest sweet spot that you are likely to find, thus, getting an AR configured like that is the easiest to get shooting accurately and reliably with the least amount of work on the firearm and at the load bench.
There are very few ARs in Whisper with anything shorter than a 16 inch in a general sporting arm for just these reasons.  SBR Whispers are rarely used for anything other than sport shooting or, in a few select cases, urban population deer or varmint control.
 Most Whisper shooters intend to put a suppressor on their firearm sometime in the future, but the reality is that few ever really do. If you get the most flexible set up, you can learn about the cartridge, hone your loading skills, and use the firearm while taking your time to research suppressors and budgeting the money.  You can also take this time to research the NFA and decide if having your barrel shortened to less than 16 inches is for you.
 There are quite a few Contender barrels out there that are pistol length, but they don't have a bolt/carrier assy to cycle, so the dynamic of their set up is radically different!

* I really like the idea of the carbine length over the pistol length. Like you said parts are easily available. Can you reliably run both heavy subsonic through light supersonic loads with just a gas tube adjustment using the carbine length gas system on a 16" barrel, or is there more to it?
 Yes, that is how it is usually done, with a carbine length adjustable gas tube. I've messed with adjustable blocks and tubes, and I find the tubes infinitely better than the blocks. The trouble with adjustability is that you can tune yourself right OUT of function and reliability, so it is important to make only one change at a time, in small steps, and record the results.

That said, here is the normal approach:
1) Find a reliable, accurate supersonic round to prove out the action and set the gas tube. Make plenty of them! Record the gas tube setting. This is usually a bare muzzle load, although a supersonic load shot through a suppressor will also dampen the noise somewhat, and change the tone. This will also be your cheapest load to shoot for sport, as it is usually with considerably less expensive conventional bullets. This is usually branched out to include paper punching loads and game loads.
2) Screw on the can, and develop a reliable, accurate SUB sonic round. Tune the gas system for reliable cycling and record the setting. This will be your most expensive load to shoot, as it's usually loaded with 200-240gn Sierra HPBTs, which are pricey no matter where you get them from.  Tuning your subsonic load without the can attached is a fruitless venture, as the dynamic of an suppressor dramatically changes the harmonic point of greatest accuracy and carrier dwell time.

 Most people have only 2 loads, both of them their accuracy loads, and only two gas settings. Usually we mark these with little gouges or dots on the hand guard to align the adjustment screw of the tube (which pokes up some from one of the holes in the top hand guard). Then, as a back up, record your gas settings on a piece of laminated card, and put an Allen wrench or small screw driver (whatever your adjustable setting uses) in a piece of foam and put it in your buttstock. You'd be surprised how many times this little thing will save your butt and reputation at the range when switching ammo and demonstrating how COOL your new toy is!!!!!
 As an aside, tuning for accuracy or function with your sub sonic loads is WORTHLESS without the can that you plan to use attached. The can changes the time/pressure curve of the gas system and the harmonic of the barrel. You may be able to use an accurate sub sonic load developed without the can as a starting point for a fully suppressed load, but don't count on it being a performer in the long run without more attention to load development.

* What is the better barrel, CM or Stainless?
 Ford, Chevy, or Dodge. All the current barrel producers are putting out some very high quality tubes currently. I suggest Stainless, due to it’s inherent wear properties, but CM may fit into your budget better or meet your finish requirements. Many people want a black phosphate barrel on their AR, and this can only be done on CM steel. The other option is to KG (or other similar coating) coat a stainless barrel. Talk to your gunsmith and budget accordingly.
 Either way, as long as you understand that no two barrels are the same, a CM and a Stainless barrel, both from the same manufacturer, will usually shoot to the same overall potential.
 Get whatever suits your fancy and is appropriate for your platform and final finish requirements. I own both, and they all shoot well. I have barrels that are stainless, CM, KG coated and parkerized. I haven’t worn one out yet.

* I am really reconsidering this project, because you keep talking “Reliability and accuracy”, is the Whisper really that hard to get working right?
 No, please do not get discouraged. The Whisper is a great first wildcat cartridge, easy to make from readily available parts. The same holds true for loading your own cartridges. It is a wonderful, light recoiling cartridge with a lot of utility.
 On top of everything, it is one of the first “Alternate caliber” uppers available for the AR, and the only one that uses ALL of the components of the original system in basically unmodified form except the barrel! Same bolt/carrier, same magazines, everything!




General loading FAQ

* Where can I find loaded rounds for my Whisper?
 Whisper almost REQUIRES hand loading by you, the user, and not a third party, if you are going to get the maximum advantage from it whether you are going super or sub sonic. If you're not going to hand load, I would suggest you search for a more conventional cartridge to get done whatever it is you want to do.
 Love it, hate it, or don’t really care, CorBon is about the only place that loads Whisper for over the counter sales. Only you can decide if it is right for you.

* OK, I guess that I have to hand load. I have looked all over the web for components, but Whisper brass is not only is it hard to find, but it is expensive. How do I form brass for my Whisper and get the cost down some?
 There are 2 basic methods. One is to form them from 222/223 Remington cases, and the other is to form them from 221 Fireball cases. What you have to ask yourself if “How much work am I willing to do to get the best brass possible?” Both methods have their pros and cons, and both require about an equal amount of work and attention to detail to get high quality, accurate. REUSEABLE brass.
 Likewise, both methods require you to know what the dimensions of the chamber are that you’re going to use them in. PAY VERY CLOSE ATTENTION TO THE FINAL NECK THICKNESS AND LOADED ROUND DIAMETER, especially after seating a bullet. If your tolerances are too tight (Benchrest comp guys consider .002 to be “good” but that is way too tight for anything other than a $3500+ full BR rig. I suggest targeting something on the order of .005 for a bolt gun and about .010 for an AR platform. Both of these measurements are for sporting arms. Consider a wider tolerance for a field gun. Naturally, if you have more than this without neck turning, you basically have no choice but to live with it. If you have less, you may need to neck turn your brass for reliable feed/function in your firearm.) Most factory arms have a chamber that will be about .008-.015+ over loaded cartridge diameter, with AR platforms often more than that!
 Also, there is the economics of the equation. The cheapest Fireball brass will go for about $.21 a case, 222 Rem $.15, and 223 Rem $.12. Naturally, using premium brass, such as Lapua or Norma (both of which I recommend for any bolt action Whisper) will go for about $.63 a case. The tools (dies, micrometer, annealing kit, primer pocket uniformer, flash hole deburrer, etc.) are all the same, so get the best that you can afford the first time, even if this puts your time schedule behind where you want to be. Trust me, you will appreciate it later.
 NEVER pass up the opportunity to purchase another tool, and never cut yourself short on the quality of those tools. I personally have used the RCBS and the Redding die sets for the Whisper, and I have used both methods. I prefer the utility of the Redding set, but there is nothing wrong with the RCBS, or any other manufacturer, for that matter, that I am aware of. I have seen people use a Lee universal decapping die with a .30 cal expander mandrel in it produce great brass, and I have seen some really poor QC on the best of custom dies. I know that SSK’s web page says that they’re the only one authorized to allow anyone to make dies for this cartridge, but in practical terms, they are all compatible in the real world. The acid test comes when you compare your newly formed brass to your chamber. Evaluate if for yourself using all the normal criteria.

 First, a word on annealing. This is not intended to teach you how to anneal your Whisper brass, but rather to illustrate to you the reasons why you should consider it.
Many people fear this word, and this process. Brass is a metal that hardens through cold working. That means that the more you expand or contract it in your dies, the harder it will become, until over time it’s “springiness” will be gone, and it will be too hard to work as a casing effectively. Commonly, neck tension will decrease markedly (sometimes lacking the ability to hold a bullet) and/or the necks will split upon resizing or firing.
 You can see a gray/brown ring on your new cases on the neck and shoulder. This is factory annealing, and can be polished off if you do not like the cosmetics of it.
When you form using 222/223 cases, you are forming a neck on a full hard portion of the parent case body. This new neck MUST be annealed to soften it up if all of your careful work is to last more than a use or two. Indeed, with some brands of brass, newly formed 222/223 cases will not even have the ability to hold a bullet. They must be annealed to work effectively.
 When you form using 221 Fireball, you are expanding the neck in an area that has already been annealed. But by cold working it through expansion, you effectively take about half of the life out of it.
 There are several methods of annealing brass. It is not rocket science, but if done incorrectly could, at best, ruin a lot of brass. At worst, you’re dead from a KaBoom.
I suggest that you use the Hornady Annealing Kit. Cheap insurance. It uses Tempilaq, a temperature indicating paint, to show you when you have reached the proper temperature. This will help keep you safe if you follow the directions included in the kit to the letter.
If you search for annealing of brass on the web or on the gun pages, you will eventually find a version of this: “In a dark room, use a propane torch to heat the brass neck to just past warm orange, but not quite red, then simply dunk in cold water, all while holding it with a stick/coat hanger/shish kabob skewer”. Medieval metal smiths and armorers trained for years to recognize the proper color of steel when heating to harden it properly. Years of trial and error, and they still were at best inconsistent. Ask your self if you are comfortable enough to be willing to play “Bet your Life” on your skills of “reading the red”, especially for a beginner. “That’s how we’ve always done it, and I’ve never had a problem” is pretty poor advice to a beginner, and rather slim rationalization for an old salt, especially in light of cheap and easy to use tools to GET IT RIGHT EACH AND EVERY TIME, as well as ENSURE A WIDE MARGIN OF SAFETY.
 Commit to doing it right. The firearm, and possibly the life, you save may be your own.


ALWAYS USE PLENTY OF IMPERIAL SIZING WAX OR EQUAVILENT FOR ALL OPERATIONS INVOLVING THE USE OF A DIE.

DO NOT USE NICKEL PLATED BRASS UNDER ANY CIRCUMSTANCES.


**Adjust the following instructions as appropriate to your dies. Always read and follow the die manufacturers instructions to the letter.**

----Method 1, forming from 222/223 Remington (often called the “Benchrest method”):
Since the parent case, the 221 Fireball, has the same case head dimension as the 222/223 Remington, it’s quite the obvious easy conversion. The Redding die set is preferred for this method. I prefer to use a form/trim die first, but it can be done reliably without one.

1.Set up the sizing die, bottom of the die just past snug against the shell holder, REMOVE the decapping stem. Remove.
2.Set up the form/trim die, bottom of the die just past snug against the shell holder.
3.Lube the outside of the case thoroughly.
4.Raise the case into the form/trim die with firm, even pressure, to the top of the stroke. Remove the case.
5.Install the previously adjusted full length sizing die.
6.Raise the case into the full length sizing die with firm, even pressure. Remove the case.
7.Remove the case lube by your favorite method.
8.Trim to length +.020.
9.Anneal.
10.Lube brass, reinstall the neck expander stem, and size in the full length die.
11.Remove lube by your favorite method.
12.Trim to final length.
13.Prep and load as normal brass.

Pros:
1.High quality parent brass available.
2.Cheap and readily available .223 cases.
3.Easy to produce quality, consistent brass.
4.Neck thickness and concentricity is very consistent.
5.Easy to control overall length of the final product.
6.Can be done in batch operations. (Step 3x100, step 4x100, etc.)

Cons:
1.Time consuming.
2.May require neck turning for proper chamber clearances.
3.Multiple trim operations.
4.Requires annealing to get more than 1-2 uses of each piece of brass.

Notes on Method 1: This method, as described above, produces the best quality, most consistent Whisper brass that can be had. Period. End of conversation. It takes forever, however, to make 100. Bolt gunners and pistol shooters usually use Method 1 because these platforms allow much tighter control over the spent casing, and there is generally a higher degree of accuracy demanded of these arms, as well as a premium price paid.
I use a 2 step trim method for two reasons. First, by cutting the brass oversized initially, you have protected the eventual final case mouth, the last part of the brass that the bullet encounters (it’s as important as the crown on the muzzle, and you’re protecting that like the Pope, right?)
 I use a 3 step sizing method, as the final sizing will serve to “iron out and even out” any minor differences in the annealing, shoulder position, and neck concentricity. That neck has had a lot done to it since you first formed it, and I see it as cheap insurance to ensure a consistent, quality case.
 Most people do not perform steps 2,8, 10, or 11, preferring instead to simply size, trim to final length and anneal, then load once cooled. Once you have gone to this much trouble, why not uniform the primer pockets and deburr the flash hole, too? Your choice.

----Method 2, forming from 221 Fireball (often called the “Easy” method):
This is the easiest method, by far, but just as full of problems as Method 1. Bulk shooters, a la the AR, usually use Method 2. Again, I prefer the Redding die set, with its two floating expander mandrels: The first from 22 to 7mm, and the second from 7mm to 30 cal. They float slightly, and minimize off center expanding. I have seen good results with a universal decapping die from Lee with one of their new progressive expanding decapping rods used in one pass, but I do not use this method myself.

1.Set up the sizing die, bottom of the die just past snug against the shell holder, REMOVE the decapping stem. Remove.
2.Set up the expander die, bottom of the die just past snug against the shell holder, the appropriate expander mandrel inserted.
3.Lube the inside of the case neck thoroughly with sizing wax and a cotton swab.
4.Pass the case through expander #1 with firm, even pressure.
5.Replace the decapping stem with the second one if you are using the 2-step expander method.
6.Re-lube the inside of the case neck.
7.Pass through expander #2 with firm, even pressure.
8.Install the previously adjusted full length sizing die with the final expander mandrel installed, usually the same one from step 7.
9.Lube the outside of the case thoroughly.
10.Raise the case into the full length die with firm, even pressure, to the top of the stroke. Remove the case.
11.Remove the case lube by your favorite method.
12.Trim to length +.020.
13.Anneal.
14.Trim to final length.
15.Prep and load as normal brass.

Pros:
1.Fast.
2.No need to turn necks, as they are usually fairly thin.
3.Can be done in batch operations. (Step 3x100, step 4x100, etc.)

Cons:
1.Expense of 221 Fireball brass, approx 2x the cost of .223 Rem.
2.Rarity of 221 Fireball brass, only made by Rem.
3.Inconsistency of 221 Fireball brass, varies in quality from lot to lot.
4.Thin necks.
5.Attrition rate of about 3-5% from split necks.
6.Attrition rate of about 10%+ for off center expansion.
7.May have brass that is unusually short due to brass shrinkage from expanding, which could lead to premature throat wear.
8.Requires annealing to get more than 3-5 uses of each piece of brass.

Notes on Method 2: This is definitely the bulk loader’s way to do things. This method, as described above, produces the best possible LOW quality, marginally consistent Whisper brass that can be had. It is fast as all get out, though, especially if you expand in only one step, and only cull out the splits. I see a lot of AR shooters make lots of brass this way, but not all of them! The AR can be hard on brass, rotating it upon extraction, and slamming it against brass deflector, and then ultimately throwing it 5 yards that away!
If you are not going to anneal this brass, it will probably last 3-5 uses, depending on your chamber dimensions and how violently your gun treats its empties.
 This method will cause the uneven expansion of the case neck walls in about 15% of your brass. This is due to the normal inconsistencies from case to case, and many of them will have tilted necks, making the case mouths out of square with the case head. SOME of this can be ironed out in a final sizing and trim, but I’ve never seen it totally get rid of it.
 Again, this method uses a 2 step trim, but depending on the quality of the lot of 221 that you are using, you may, and often do, end up with cases that are a little short of optimum, and they will not need trimming for a number of firings.
 This is the method that most first time loaders use, as it is fast, easy, produces about 75% good cases, no annealing is generally required initially, and the rationale that the “AR is so hard on brass, it’s not worth all that trouble”. Bolt gunners and pistol shooters will see a marked drop in accuracy with Method 2 over Method 1.

 If you end up having to turn necks, or simply choose to, some of the best tools to do the job quickly and accurately are available from Sinclair, Intl.

* I have a Whisper, I’ve made some brass, now how much of XX powder should I use to get an MOA subsonic load?

DANGER, WILL ROBINSON, DANGER


 First off, there is not enough information there to suggest a starting load point from anyone. Be wary of anyone that offers you loads without telling you what you should have told them about your gun, namely: barrel length, twist, type of arm (bolt action, pistol, AR), super or sub sonic load, and any specifics of the arm (suppressor (length and type, adjustable block/tube, etc.), and what brand and configuration of bullet, as well as the weight of that bullet, the primer brand, brass brand, and any specific brass prep steps you have taken.
 Do you want to just get the bullet out of the barrel and have it drop on the floor (I've never quite been able to do this, but I've come close a time or two!), or do you want to get MOA out to 300yds? Either goal will take some tuning and loading knowledge on your part.
 That said, reloading based on getting a minimum charge weight is a HUGE no no, especially with the Whisper. Using pistol powders in minimum loads leads to loads with less than ~80% load density. What happens is that the cartridge lays over in the gun, and under successive recoil, the powder distributes evenly along the lowest point, and this exposes a huge surface area (much larger than under normal loads) to the primer blast. Then you get a huge flame front inside the brass, and pressure spikes much faster and higher than the arm is originally designed for. This can be as dangerous as a double charge of powder. KA BOOM!!!
 There have been tons of 38/357 revolvers destroyed this way by pin shooters using minimal charges of Bullseye and Red Dot, and plenty of 9mms and 40 S&W blown up the same way. I happen to have a very nice, stainless 44 S&W that I got for $50 because the owner had blown the cylinder open and the top strap off with a micro load of Bullseye!  I keep it to show new reloaders the false economy of trying to get the cheapest loads possible.
 To reload reliably super or subsonic for the Whisper, get a chrony. Doesn't matter which one, as they're all "general" devices anyway (unless you’re willing to invest in or have access to some of the nicer high end units), accurate enough to evaluate information such as velocity +/- a little. Just remember not to compare information gained from your chrony to information gained from someone else’s, they all individual machines, with individual tolerances.
 Based on my experience, I agree that nothing faster than AA#9 should be used in an AR platform, and the Contender barrels, being of pistol length, generally like different powders than the rifles do.

* You won’t give me any load data, and I understand your safety points, so where can I find that information for my Whisper?
 You need a load manual. Would you work on your car without the proper tools and safety equipment, would you? Consider a load manual one of your best safety devices. They catalog loads that have proven within safe pressure levels and list the information that I outlined above that is necessary to ensure compatibility. It is up to you to compare the firearm used in the load manual to your firearm and evaluate if the loads are going to be right for you.
 From there, it is all trial and error, as each firearm in an individual, just as in any other caliber.
 The latest Sierra and Accurate Arms manual both have Whisper loads, and most of the powder manufacturers have loads posted on their web pages.

* What should I load for first, accuracy or velocity?
 Search the web for Optimal Charge Weight. Follow this method and load for ACCURACY first, then you will be able to tell (with the aid of a chrony) if your accuracy load is below the sonic level for a given combination or super sonic. After all, who cares how quiet it is if you have to shoot a dozen of 'em to hit anything?
 If you are trying to get subsonic through a suppressor, and the accuracy load you find is not quite subsonic, you are going to have to make a decision as to what level of accuracy you are willing to accept to get quiet or what level of sound you are willing to accept to stay accurate! It is inherently a trade off, but you should be able to find at least one very accurate load that is sub sonic.

* What level of accuracy can I expect from my Whisper?
 Whisper is generally considered to be a 1MOA capable cartridge. In fact, seeing as most firearms are made from better quality components in relatively low volume for the Whisper, as a whole they tend to shoot, with careful load development, at least MOA.
Generally, your super sonic loads will be pretty easy to get accurate, but the sub sonic ones will take a bit of work. Careful attention to the method in the Optimum Charge Weight method will help you zero in on the sub sonics quickly with a minimum of wasted materials and time.
 It is a function of stability, bullet weight, and velocity. Long, (tail) heavy, sub sonic loads are just a little finicky, especially if the wind is blowing. Don't believe me? Put in a 1050fps 240gn Sierra HPBT Match King zeroed to 300 yds into your ballistics program, then throw a 10mph cross wind at it and just watch how much it drifts (or drops, for that matter, compared to a 100yd zero)!!!!!!!!! Super attention to detail when setting up necks on the brass and minimizing run out on the bullet upon seating are CRITICAL to a successful load.

* What bullets should I use for super and sub sonic loads?
 Another Ford, Chevy, or Dodge debate. Use whatever shoots the most accurately in your firearm. Try everything. Talk to your buddies, and each of you split the cost of a box of bullets and powder!
 The de facto standard for accuracy loads in sub sonics, though, are the heavy Sierra Match Kings.  Great results have also been achieved with Hornady and Berger bullets.

* What shoots better, super or sub sonic loads?
 Both can be made to shoot to a very high level of accuracy in the Whisper. Super sonics will be easier to develop and fine tune. Sub sonics will be a little harder, but they still have the same accuracy potential.

* How much noise does a sub sonic load make?
 The noise that your gun makes is a function of muzzle blast and sonic bullet crack, coupled with any noise generated by the action cycling (the lack of which is what makes suppressed bolt guns REAL quiet!). With a sub sonic, at least half of the equation is not present.
 Ideally, 99.99 percent of the powder used to propel the bullet will be burned up inside the and fully expanded. This will leave very little hot gas expanding following the bullet out of the barrel and generating the blast. In reality, this type of result is all but impossible to achieve, and there will be some muzzle blast.
 In practical terms, the sound level of a sub sonic load without a suppressor is usually described as “Half that of a .22LR”.
 From a shooter’s point of view, the muzzle blast is minimal, the gun movement almost non existant, and cycling fairly soft.  In fact, even with supersonic loads, most bolt shooters report being able to hear the “ping” of the firing pin as it hits the primer and bottoms out on the firing pin stop!

* What can/suppressor should I use?
 Not to be repetitive, but that is another automaker debate! Search the web, call on the phone, and talk to owners in the real world. If you can, and if you are lucky enough to have one close, talk to a local shop. Sure, they’re all going to try to sell you a product to some degree or another, but at least you will be able to actually handle some of the various models and evaluate them for yourself.
 The biggest piece of advice that I could give you on this is to EDUCATE YOURSELF BEFORE BUYING. It would be a terrible shame for you to have done all of the work researching and buying a firearm, buying load equipment, developing loads, and purchasing a Federal Tax Stamp item only to be disappointed and out $500+ for a can that you really do not like or does not fit your application.
 Generally, though, the companies that produce and shops that sell suppressors have a vested interest in getting you the right product the first time. After all, a happy customer that shows off his new toy is great advertising.
 Here again, I can’t stress this enough.  LISTEN TO YOUR GUNSMITH.

* How much recoil is there with such slow and heavy bullets? How about the supersonic loads?
 Due to the light loads and generally small volumes of powder, most people describe the recoil of the Whisper sub or super sonic as “About like a .22LR”.
Link Posted: 1/3/2006 6:33:59 AM EDT
[#3]
Thanks a lot.  That is great stuff!  But one little question - on the optimum twist rate paragraph, you actually give the *mininum* 'fast-ness' of 1 in 8 for 200-240.  Do you have any more information on what would be the true *optimum* for the heaviest 240s doing 1050?  1 in 7, 6, what?  Anyone know?  Thanks.
Link Posted: 1/3/2006 8:52:20 AM EDT
[#4]

Quoted:
Thanks a lot.  That is great stuff!  But one little question - on the optimum twist rate paragraph, you actually give the *mininum* 'fast-ness' of 1 in 8 for 200-240.  Do you have any more information on what would be the true *optimum* for the heaviest 240s doing 1050?  1 in 7, 6, what?  Anyone know?  Thanks.



OK, here's the simple answer for you:  Probably no one CURRENTLY (as of 03 January 2006)knows when it comes to super or subsonic what the "OPTIMUM" twist is going to be for the long, heavy 30 cal bullets.  1/8 works and works well with the current range of cartridges and bullets, so there's not a lot of "need" to push the boundaries.  If anyone does know, I'd be interested to see the methodology, rationale, and results.  As a theory, I offer this:  The optimum twist is the slowest at which you achieve your desired level of accuracy for the range that you are shooting, your desired velocity, and acceptable component life without sacraficing safety.

One other thing to considder is that historically, the optimum accuracy is produced in a firearm set up when the projectile being fired is spun only just fast enough to stabilize it thuroughly from the muzzle to the intended target.  Increasing that spin above a certain threshold has proven detrimental to accuracy and precision, as well as component life to some extent.  As empirical evidence I submit to you the rifles of Benchrest shooters of all disciplines from 100/200/1000 yard and varmint for score.  I don't think that many rational persons would argue the fact that these precision crafted rifles and carefully tuned hand loads represent, as a fraternity, the most accurate and precise firearms currently available to today's shooter and the cream of the crop of the gunsmith trade when representing pure accuracy and precision.  (Accuracy=hitting your intended target every time, Precision=hitting that target in the EXACT SAME HOLE every time.  Many rifles are accurate, very few are precise).  ALL of them use the slowest twist possible to stabilize their chosen bullets.  If fast twist was the ticket, every 6PPC shooter would be shooting a 1/8 instead of a 1/14, but this has not proven out true on the targets.  Maybe we're talking like the difference of 10ths of an inch at 100 yards, but it's enough of an axiom that I've seen it in print more times than not.  Now, the 1000 yard shooters do choose the faster twists, but no faster than is needed to stabilze their bullets supersonic through the target.

Referencing the web sites for Broughton, Douglas, Hart, Kostyshyn, Krieger, PacNor, Shilen, Spencer and Lilja (thats 9 of the top barrel manufacturers anywhere!)we find that only Broughton and PacNor offer anything faster than a 1/8 in their 30 caliber line and some (Krieger and Douglas) only mass produce 1/10 or slower in 30 cal!  K and D may make special runs of faster twist, but they're not advertised as regular production on their web pages.

Taking all of the above into account, there may be an optimum twist for subsonic long-for-caliber bullets, and it may prove out to be 1/8.  We know NOW that it works effectively, so again, there's little need to change other than the pursuit of knowledge.  I'm not saying that faster isn't necessarily better, but carefully weight the added cost/availability limit of other than standard components to your desired goal with the gains you would achieve from them and the necessary trade offs that occur in a firearm system.

I hoipe that this answered your question.

Tom  


ETA research on the barrel manufacturers.
Link Posted: 1/28/2006 2:11:32 PM EDT
[#5]
What is the maximum range that can be had from these bullets with still being accurate and lethal?
Link Posted: 2/10/2006 8:46:36 AM EDT
[#6]
Link Posted: 2/24/2006 12:50:34 PM EDT
[#7]
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