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7.62x40mm Information Thread (Page 4 of 35)
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762x40 : I have started to round up everything I will need for the reloading components. One of the bullets I picked is the Speer Varmint 130 grain H.P. #2005. Have you or others that are loading for the 40 tried this bullet yet. Its profile is a lot like the Sierra 110 gr. H.P. and actually has a shorter o.a.l. (.887") than the Speer 125 gr. TNT at .950" . Joe |
Sorry, thats one that I haven't tried.....I have used several of the Sierra 110 HP Varminter #2110....If it has a similar profile it should work great.....the earlier reloading data posts show the Hogdon H4227 works pretty good on the 135's but starting to run out of case capacity....I have been told that the H4227 has been discontinued but the IMR 4227 is going to remain available....the IMR should be a little bit hotter, may help on the capacity side....working on getting some to try, I'll see if I can locate some of the Speer 130's to try for ya..... 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
My drill guide bushing hasn't shown up to drill the gas port yet. I've got some 110g V-Max loads ready to go for it. |
In a pinch, I have sacrificed a Model 1 steel gas block to use as a guide bushing....ended up tapping, threading, and plugging the hole I made in the top and using the block on a test build  Thanks again, 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
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762x40 : With all the different loads you have tried so far is there a powder that you feel works best in the 40. Or are the powders in the burn class you have been using pretty much equal. I ask this because when working up loads for a cartridge there are things that show up other than just velocity and pressure signs. Things like how clean the powder burns and the feel of the action during its cycle and so on. Joe |
Thanks for the support........I understand and appreciate your frustration.... I have intentionally stayed out of the 39 threads....the cartridges are totally different and have different AR platform mechanical requirements, the 39 several, the 40 one.......both the 39 and 40 have had their teething issues adapting to the AR platform....I have been fortunate enough and blessed to have been able to hyper focus on the 40 and work out the problems with relatively easy fixes in a short amount of time.....had a very good starting point with the 300 Whisper, thanks JD tooling and die work is expensive, so I realize that the numbers of and interest in the AR 39's had to come up over the last several years to a point that the justification was enough to support manufacturing of improved bolts and magazines.....These issues, in my own opinion, should have been rectified day one by the AR manufactures before the rifle was released to the public....I think the 39 is an excellent cartridge and has performed admirably, although infamous in some roles on, I think, every continent on this planet.......In my opinion it is this service and the following it has created that has kept the adaptation to the AR platform alive....I can think of a half dozen or so systems (rifles, pistols, and machine guns) that have died because they broke parts or had magazine issues.....but even with the problems adapting to the AR the 39 forges on because it is everything it has earned over the last 60 years or so..... Anytime someone compares (good or bad) the 40 to an industry established cartridge like the 39 or .30-30, I think it's pretty neat, considering the 40 is a wild-cat that was dreamed up in a travel trailer.....hurricanes suck.... Thanks all, 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
different results for 16 or 20" barrel.....the 1680 seems to work best in the 20"...... I'm really starting to like the versatility of the H4227 in the 16" barrel...it doesn't produce the absolute highest velocities but has a solid pressure curve across 110 to 155gr bullets....cycles very positive across different load density.....The IMR 4227 is only a little bit faster than the H4227 so I think it should be very close to being my go to powder......I'm not a big speed junkie so I'll probably leave the faster lil-gun, H110, and W296 to the SBR applications.... All of the powders tested are pretty fast compared to conventional rifle powders....they all burn pretty clean....the one thing that I have noticed is that W296 is very consistent, small extreme spread....the others spread seems to get better as the load density comes up but the 296 doesn't seem to be as sensitive to load density.... ease of cleaning: the thing that I have noticed cleaning after trying the different powders is the residue color runs from black to black/green to black/red.....no noticeable difference in amount, just the hue...the 296s' red hue seems to be most noticeable on the ring / cylinder junction and carrier vents.....if you look real hard at the pic of uptown1's rifle in the opening post you can see what I'm talking about around the carrier vents.... I really like the 1680 in a 20" and 4227 in the 16"....... just as an aside, you get the most bangs for your bucks with the faster powders in the 110 to 125gr 16" barrel loads.....smaller charges to hit a target velocity of say 2,400fps.... shooting technique: a couple of the guys that are using the 125 TNT's regularly shoot them over 2,500 fps using H110.....something to remember when using a temp sensitive powder like H110 is heat soak.....if you running a max charge and fire say 20 rounds rapid fire and heat things up pretty good and let round number 21 sit in the chamber for a couple minutes and then cap it off you're going to get max charge pressure+++ temp gain.....just leaving H110 loaded rounds in the sun can make them go high pressure.....don't seem to run into this with the slower powders like 4227, about all you see is a small velocity increase... Hope this helps, 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
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762x40 maybe this has already been asked, but have you had any issues with neck thickness on your 40 brass. I was also wondering what kinds of brass you have used. Also do you have any thoughts on how to get a power trimmer set up for the 40. So far Ive heard the lathe, the drill press and the good ol manual style trimmers. I'm looking at doing several thousand cases, so I need a fairly efficient setup. I hear you can get a Giruad trimmer set for 300 whisper. That was sounding pretty cool. I was also wondering about modifications needed for the Pmag to fit the 40. -Kag |
Brass that I have used, lets see......Winchester Commercial, Winchester Military, Federal Commercial, Federal Military, Lake City, Partizan, Fiocchi, Norinco, PMC, Remington, and IMI.......I intentionally used range pick-up to test several brands for neck wall thickness.... the 300 Whisper was designed around .221 parent brass, by the time the .221 is necked up to .30 the neck walls are pretty thin .008 to .009, the Whisper chamber was designed to use this thinner neck brass, if you use .223 brass you end up with slightly thicker neck walls and can run into problems in the tighter Whisper chamber.....although, both of my newer SSK 300 Whispers work fine with .223 brass ammo....the AR was actually supplied with LC .223 based ammo....maybe the Whisper chamber design has been opened up a little?.... from the start the 40 was based on the .223 parent case....the .223 brass I tested has a starting neck thickness of between .0115 and .0135.....by the time it is cut back, formed, fire-formed, and gets flowed a couple times the neck thickness ends up around .0105 and .0115....and the chamber was designed to allow for this.... I believe Keith Davis (of 300 whisper brass manufacturing fame) used a Dillon to mass produce brass.... When I started messing with the 300 Whisper everything I read and was told was that it used standard unmodified mags....when I ordered my first 300 Whisper AR from SSK it came with two modified metal mags, about 2" of the ribs had been milled out, the followers had been changed, and the spring had been shortened....apparently my definition of unmodified was a little different than JD's....but I started to appreciate the genius of these tweaks and what they did.....by removing the couple inches of the ribs at the top of the stack it allowed the rounds to spread out at the top of the mag before they came in contact with the mag lips.....by changing the follower out it kept it from flipping over in the area where the ribs had been removed....shortening the mag spring reduced the amount of pressure the cartridge stack put on the bolt carrier during cycling, made it cycle slick with subsonics....you can use standard mags, but the tweaked ones work better...... As with the 300 Whisper and other wild-cats including the 40, un modified pmags will work, modified pmags work better......if you remove between 1/2 or 3/4 of the rib thickness it allows the rounds to spread out a little and reduces the cartridge stack tension....I have found a couple ways to do this, one can be done using a 'perma-grit' sanding bar, lay the mag on its side and file it out.....another way is using a stock inlet tool, use the diameter for the amount of rib you want to remove, lay the mag front side down or hold vertical and pull the inlet tool across both ribs, it cuts both at the same time....I'm going to the range today to test some lil-gun loads for the 40 using unmodified 20rd pmags, when I get around to it I will probably modify them like the others......by reducing the stack tension and shortening the spring, like the SSK mags I have, It makes the pmags more applicable to subsonic use.... Hope this helps, 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
Lil-Gun Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow) Test Rifle 7.62x40mm 16" 1:8 Olmypic .078 gas port carbine length gas system, fire-formed brass... 125 TNT 17gr lil-gun = 2,174 fps 125 TNT 17.5gr lil-gun = 2,220 fps 125 TNT 18gr lil-gun = 2,266 fps 125 TNT 18.5gr lil-gun = 2,317 fps 125 TNT 19gr lil-gun = 2,372 fps 125 TNT 19.5gr lil-gun = 2,410 fps 125 TNT 20gr lil-gun = 2,430 fps I don't usually gravitate to the real fast powders but the lil-gun should work really well in a pistol or SBR....not my favorite for the 16".... Hope this helps.... 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
Today Range Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow) Test Rifle 7.62x40mm 16" 1:8 Olmypic .078 gas port carbine length gas system, fire-formed brass... left the powder charge the same at 22.5gr H4227 and varied the bullet weight and style... 110 RN 22.5gr H4227 = 2,440 fps (M1 carbine round nose) 110 PSP 22.5gr H4227 = 2,430 fps (hornady pointed soft point) 110 HP 22.5gr H4227 = 2,444 fps (sierra varminter) 110 V-Max 22.5gr H4227 = 2,497 fps (hornady V-Max) 123 FMJ 22.5gr H4227 = 2,412 fps (lapua fmj) 125 TNT 22.5gr H4227 = 2,420 fps 135 SMK 22.5gr H4227 = 2,391 fps These are averages of 20 round strings... Thanks, 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
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762x40 It's great to see all the loads you have working so far. Ive looked a few places and can't find H4227 anymore.hock.gif Hopefully the IMR 4227 will be comparable. I was looking at a burn rate chart and looks like IMR, Co SR4759 is between H4227 and 1680. I don't have any experience with these powders. I was wondering if you had tested the 4759 or if its out of consideration for other reasons. This will be my first Wildcat, I'm used to having reloading manuals to go off.hing -Kag |
I haven't used any of the SR4759 but the burn rate looks good, not sure about the density....but it looks within the range of powders that I have used, I'll try to find some local to see what it looks like....I tagged a list of powders from my burn-rate chart, let me know if it falls in line with yours.....top powder on the list being the faster... Lil Gun (Hodgdon) 30 Carbine (Rottweil) R123 (Norma) PCL 512 (PB Clermont) NOB-89 (Nobel) SP3 (Vectan) R910 (Rottweil) S265 (Somchem) REV-1 (Nobel) H110 (Hodgdon) REV-3 (Nobel) BA6 (Vectan) 296 (Winchester) AR2205 (ADI) SR-4759 (IMR) N120 (Vihtavuori) 4227 (IMR) RP1 (Bofors) R901 (Rottweil) H4227 (Hodgdon) 5744 XMR (Accurate) 410 (Alliant) RIF-3 (Nobel) N130 (Vihtavuori) SP-3 (Vectan) 680 (Winchester) N200 (Norma) PCL 508 (PB Clermont) 1680 (Accurate) Thanks, 40 |
Hopefully the IMR 4227 will be comparable. I was looking at a burn rate chart and looks like IMR, Co SR4759 is between H4227 and 1680. I don't have any experience with these powders. I was wondering if you had tested the 4759 or if its out of consideration for other reasons. This will be my first Wildcat, I'm used to having reloading manuals to go off.
I've got almost everything figured out. looks like I'll be going with a Dillon 650 and modifying the trimmer die to cut to 40 length. Should be great if I can get it to work. I just need some custom dies and a barrel.
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
The 135 SMK at 2,400 fps is more than a little bit inspiring, especially coming from a 16" barrel. These folks couldn't break 2475 with a 125g in a .308x39, in a 25" barrel bolt gun. AccurateReloading.com's 25.5" .308x39 Load Data Why again am I waiting for a 7.62x39 magazine that works? |
not trying to kick an ant mound, but my little old 24" 300-221 bolt-gun regularly shoots 125 TNT's over 2,500 fps....the powder column increase and improved case geometry of the 40 bolt-gun that I'm building should put it past that........I had looked at the .308x39mm data before and I thought I remembered there being a couple loads around 2,500, I'll have to go back and look again....my 20" Noveske 40 AR will shoot 125 TNT's a little over 2,600fps
I hope they work....I know a couple guys that are waiting on some.....one told me today if they didn't he was going to switch teams, after he dumped a 30 round mag of 135's and figured out all he would need to do is change the barrel on the upper he already had... Thanks for the ballistic info.... 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
I went back and dug up some of the data on the 20" Noveske 40.....haven't shot it in a while, been focusing on the 16".... (standard disclaimer as with any wild-cat, use at own risk and work up slow) 110 HP 25.0gr 1680 = 2650 fps 125 TNT 25.2gr 1680 = 2,525 fps 125 TNT 25.8gr 1680 = 2,575 fps 125 TNT 26.0gr 1680 = 2,606 fps Thanks, 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
Just thought I would let you all know the Forster trimmer I ordered came in today. I set it up on my drill press and it works great. If you do not have a lathe this is the way to go as it makes short work of this much trimming. The collet locking setup makes feeding cases fast. Joe |
Hi Joe, Thanks for the update on the trimmer.....how much time do you think it takes to cut a 100 cases?.....looks like a slick set-up!!... Thanks again, Kurt |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
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I ran a sample of 10 cases at 65 seconds give or take a couple of seconds. So for a 100 should be able to do them in about 7 or 8 minutes. Joe more info: Just ran a second set of 10 cases at 55 seconds. So 7 or 8 minutes per hundred should be a good estimate. I was in a hurry and my math skills were off a little it should take around 10 minutes to do a 100 cases. Still pretty good through put and a lot faster than hand trimming. |
That's great news!!!.....set the die, one pull of the ram....done!.....great job.....thanks for helping everyone out and sharing the info.... 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
Thanks for the bump on the Norma.....I have always heard that Norma makes pretty consistent powders but haven't been able to find any local......I picked up some IMR 4227 to compare to the Hodgdon H4227 that I have been using..... I haven't been to Shreveport in years......I have former in-laws in the Coushatta area and we used to go to the Bosier / Shreveport area pretty regular...(friends don't let friends gamble alone kind of a thing) Years ago, like 16 or 17, there was a guy from up there and he and I used to do a little together with sub-machine guns....MAC's, UZI's, MP5's, etc.......he came down a few times for a firepower demonstration we used to put on for the local Sheriff Dept. Junior Deputy group....the kids used to get a big kick out of it, department budget constraints put an end to that.....He and I used to have RPB M11A1 .380's that were like one or two serial numbers apart, just a funny coincidence.... Thank again, 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
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7.62x40 I know there really expensive but any plans to test the 130gr Barnes txs bullets?hem -Kag |
Sorry to take a while to get back to you, I have been out of town on a fishing trip....I have used the 130gr Barnes tripple shock x-bullets in my 300-221.....the accuracy didn't bowl me over (around 1.5" at 100yds), but in the 40 you should have a little more velocity window to tune them.....If I remember right, I was pushing them somewhere around 2,300fps out of my 300-221.....I have around 50 left, I will load some up to test.....will post on them when I get a chance..... Thanks, 40 |
I was looking at them you a medium game load. They seem like they would be awesome out to about 250 yard.
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
Hi Joe, I haven't called anyone this week.....the last thing I heard was that both were moving forward.....I figure if I call them a couple times a week for a report all I'll do is slow things down....just in a holding pattern waiting  I'm pulling the parts together for a 9" barrel SBR (thanks to an ARFCOM member) and hope to have it running in a couple weeks......the gun hobby stuff has been moving a little slow around here.....enjoying a little summer time with friends and family... If the weather cooperates over the next couple weeks I'm also going to do a range results / comparrison with a guy from around here....16" Model 1 7.62x39Russian and a 16" 7.62x40mm (300Fireball rechambered).....before anyone lashes-out, this isn''t intended on being a my cartridge is better than your cartridge comparison.....a local guy has been having feed issues with his 39 AR (the straight section of the mag well still seems to be a problem with the 39) and we are going to try and help him with it and collect some data at the same time.......have had a few requests to post some video so I'll try and do that also.... Gone Fishin, 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
What is the barrel length on the AR in the top pic (the top pic in your first post on page 1)? Thanks! |
moose, I think 40 is out of town for a few days, I guess I can answer for him since that is a picture of my rifle. It is right at 17" measured from bolt face to muzzle end of flash hider. Rifle runs great. I'm wanting to build another, probably a 20" (little more velocity) Wanting to do a heads up comparison between my 39 and 40 rifles with Kurt but the new 39 mags still look like they are having shit problems, and people were making a big deal about hitting a pmag with a flat file to tune them for the Whisper or 40, atleast they work with 30 rounds. A 10 minute mod versus a 2 year wait. If you have any questions about the 40 I'll be glad to share what I have learned with mine. |
Yes, that is correct. It has a VTAC handguard, carbine length gas tube, and JP adjustable gas block. |
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Can't we all just get along...... www.65grendel.com/forum/showthread.php?t=3996 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
Thanks for posting the link, its good to know that some folks still think the earth is flat and others think it is round. The bottom line for me is wildcats are fun. Joe |
Not to keep drilling you about the same pic, but what glass is mounted on top! Thanks again! |
No problem, it's a Leupold Mark4 10X M3 TMR |
| Where can a person go about getting a barrel chambered in 7.62x40mm. I have a Remington 700 VLS that I'd like to rechamber to somthing that can shoot subsonic rounds and I like the idea of having a round formed from .223 cases as opposed to .221 fireball cases. |
If you are interested in exclusively shooting suppressed sub-sonic the case capacity of a 300 whisper would probably be my first choice, can be formed from .223........For super-sonic I have a few 40 reamers with different throat depths that I am using to chamber a couple bolt-guns, primarily super-sonic based on a 1:12 twist rate.....I have had really good luck with PacNor barrels....PM me and I'll answer what questions I can about a 300 whisper or 40 bolt gun.... 300 whisper bolt-gun 300 whisper bolt-gun performance Hopefully I should have some images and performance on the 40 bolt-gun shortly.... |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
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7.62x40 Any word on the IMR4227 I'm interested to see how well it works in the 40. I was looking at Hodgdons burn rate list and they show H4198 close to the AA1680, was wondering if that would work or if it would be to slow. Any word on the dies and barrels? Do you know if John is going to include a headspaced bolt with the barrels? -Kag |
Kag- 7.62x40 and I have been talking about the fact that Hodgdon has discontinued their version of 4227. So told him that I would do a comparison with the 300-221 Fireball So here are the results of that head to head comparison of IMR4227 and H4227 with the 300-221 fireball (a.k.a. 300 whisper). Here are my results. I would guess that the 7.62x40 would produce similar comparison. First H4227 is slightly more dense that IMR4247. The powder dispenser set to throw 18.5 g of IMR4247 would throw 19.0 g of H4227. Here are my load/velocity data from a 16-inch Noveske barrel with the gas port in the pistol postion. The bullets used are Winchester .308 147g FNJBTs. These data were shot with CCI450 magnum small rifle primers H4227 -----------------------IMR4227---------difference (H4227-IMR4227 16.0= 1869±20------------1835±22 ---------- +34 17.0= 1967±13------------1968±7 ---------- -1 18.0= 2037±41------------2043±19---------- -6 18.5= 2076±22------------**---------- --------- -- **chrono malfunction Here are some more results that I shot about 2 years ago. These data were shot from an Olympic Arm 16-inch barrel with the gas port in the pistol postion. The bullets used are Winchester .308 147g FNJBTs. These data were shot with Winchester small rifle primers. H4227 16.0= 1871±18 17.0= 1940±6 18.0= 2013±17 18.5= 2087±19 17.5= 1990±10, 1995±9, 1984±17 I also gave Hodgdon a call and talked to one of their ballistic engineers and was told that H4227 and IMR4227 are basically very similar powders and will give very similar results. The difference column seem to bear this out. 320pf |
IMR 4227 Range Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow) Test Rifle 7.62x40mm 16" 1:8 Olmypic .078 gas port carbine length gas system, fire-formed brass... left the powder charge the same at 22.0gr IMR 4227 and varied the bullet weight and style... 125 TNT 22.0gr IMR4227 = 2,355 fps 130 Barnes Tripple Shock 22.0gr IMR4227 = 2,327 fps 135 SMK 22.0gr IMR4227 = 2,340 fps These are averages of 20 round strings... As with the testing that 320pf did, the IMR 4227 looks to be right in line with the Hodgdon H4227....as the powder burn rate table shows the IMR is slightly hotter, not so much noticable in the fps but I did notice pressure signs similar to that of the faster W296 (slight flattening of the primers with the 135s) 320pf....thanks for the IMR load data....I shot a few of the 135SMK in my 24" 300-221 bolt-gun doing preliminary testing for the 40 bolt-gun....they worked out really good....thanks for turning me on to them...that 500 round box is shrinking fast.... I talked to Noveske a couple days ago and was told that the barrels could be expected in as early as three to four weeks....when I find out info on the dies I'll post it as well.. Thanks, 40 |
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
DoubleARon, The IPSC power factor has be lowered to 320. I have been able to make major power factor with the 300-221 fireball (a.k.a. 300 Whisper). The loads that I have been able to do this with are 180 gr Sierra MK to ~1820 fps (pf=327) out of a 16-inch barrel. I have also pushed Sierra PALMA 155 gr to ~2100 fps (pf=326) and Sierra 150 to ~2150 fps (pf=323) out of a 20-inch barrel. I am really interested in the 7.62x40mm because I think that I can probably get major power factor with the Sierra 135 g MK. 320pf |
DoubleARon, Bruce and I shot some speed drills with the Sierra 155 g PALMA bullets from the 20-inch barrel Ar. The increased recoil defiantly slows your times down by about 10%. So making major may not be all that much of an advantage... unless there is a lot of paper and not much steel. What my brother and I are doing now is shooting the 300-221 fireball with sub-sonic loads (150 to 168 gr bullets at ~1100 fps) for all the close in rifle stages. These loads are very soft. Yes even less recoil than the 223. For the long range stages we shoot the 125 gr at ~2300 fps. My brother was pretty successful at the Mystery Mountain 3-gun match in AZ this spring. If the shot guns had run better we would have scored higher (I will never use Winchester shot-gun ammo again). But back to the 7.62x40mm. I think that this cartridge might be worth trying at a few matches to see how it runs. 320pf |
When I said the accuracy of the Barnes didn't bowl me over I guess I should have qualified it a little.....At the time the rifle I was testing was capable of .150" groups at a 100yds, so when the Barnes shot over 1" they were out for that trial..... It was very windy yesterday so I was a little more focused on chronographing the loads than printing groups....just snap shooting the groups were around 3", fast enough to just regain sight picture and pull trigger....some of my friends have light weight barreled hunting rifles that by the time you get to 5 shots will usually shoot around 3" at 100yds, so I guess it is all about what is seen as acceptable for the platform.... I do like the design of the Barns very much, and if they expand/perform within a 2,300 to 2,400fps velocity window they should make an excellent medium game load... Thanks, 40 |
It's also nice to hear that IMR 4227 is pretty close to the Hodgdon powder. I was just wondering if you had better luck with the accuracy on the Barnes or if they are a no go?
" The only way I got to keep them Tigers busy is to let them shoot holes in me..."
7.62x40mm Information Thread (Page 4 of 35)
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