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Posted: 8/10/2004 8:40:18 PM EDT
Or just wishful thinking? I love my little black rifles,but I also feel the need for more power.I'm torn between the AR-10,and the FN-FAL.Larger bullets make larger holes,and messes.REight not power is becoming a factor in the middle east.Funny what cotton can do to a bullet.Will be following along with interest. Lonestarhinking.gif
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What "real thing"?
Rifles/uppers already sold. Magazines already sold. Ammo already sold (well, some). People on AR15.com have already been shooting and reloading it. Used for hunting? Already done. Used by some in the military? Allegedtly it's already happened. Used regularly by SF? Who knows? Replace 5.56mm for general isssue? Unlikely. Used by police/LEO? Seems likely once more guns & ammo are available. -z |
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the simple fact that I love about 6.8 is that it clears up any doubt of 5.56 has with terminal balistics...
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The 6.8 seems to have alot of potential and promise so, IMO, I think it'll eventually become a commercial success. However, with that said, I'm still wondering why remington decided to go with a 43mm case and a 27 caliber bullet? It seems to me that it would have been much easier (and cheaper$$$$) to go with a 5.56 NATO case that was necked up to take 6.5mm bullets instead of 6.8mm bullets. They could have kept the same 45mm case and increased its diameter to .264/6.5mm caliber. This would have allowed the end users (i.e. civilians and the U.S. Military) to just change out only the barrels while continuing to use the normal USGI mags and 5.56/.223 bolt and carrier group.
To make a long story short, why did remington go with a 6.8x43 instead of a 6.5x45? |
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Remington didn't decide anything.
The 6.8 SPC cartridge was developed with a laundry list of desired performance, requirements, and limitations (the primary limitation being that it had to be compatible with ARs with only a bolt, barrel, and mag change). Bullets from 6mm all the way up to 7.62 were tested, and the best performer happened to be the .277" (ala .270 or 6.8mm) bullets. The case was chosen to allow maximum case capacity while still having a fairly small case head, which was necessary so that the mag capacity wasn't unduly reduced. A 6.5mm bullet in a .223 case would struggle to perform as well as .223, and certainly wouldn't do better. The .223 case simply doesn't have anywhere near the case capacity needed to propel these larger bullets to a useful velocity. The SPC case, based on the .30 Remington case, has 17% more case capacity than .223, and it needs every bit of that. The folks who designed this cartridge included top match shooters, wound ballistics experts, senior SpecOps shooters, and two large ammo companies. Every decision and feature is there for a reason, with all of the choices tested and weighed and the best option chosen with the ultimate goal of producing the best COMBAT cartridge possible for the AR15 platform. -Troy |
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Thanks for the info, troy.
I've read about SOME of the 6.8mm's history but, up until this point, I never did know exactely why the cartridge designers decided to go with a modified 30 remington case rather than a necked up 5.56 NATO case. Now I know. Thanks for squaring me away. |
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Troy!!!!!!!! Hi guy,
I haven't read one article where the shooters have gone under MOA with this round. They all have covered terminal ballistics, mags, fps & ft/lbs comaparisons to 5.56.................but not one brought up accuracy. Is she a finiky bitch? I ask because I want one with a chromed bore that shoots as well as my AR-10A4. Well, how 'bout half as good as my 10A4. It would have groups in the .6XXMOA range. Dave S |
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REMINGTON OTM 115 GRAIN AMMO GROUPS SUB-MOA IN OUR 7.5 LB 16" 6.8 SPC AR' VARIANTS. TO MY THINKING, CHROME LINING IS NOT A REQUIREMENT AT THE 6.8 SPC VELOCITIES.
WES GRANT M.S.T.N. |
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But Wes. What about all the other reasons why all the "hard core" people on here say "go chrome or go home"? Chrome bores don't rust. Chrome bores are easier to clean. Chrome chambers extract easier (less wear on the extractor). Yada yada yada . . . |
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With reloads, my holes are touching at 50 yards. I haven't done much real "bench" testing yet, just load development with the chrono. I don't expect any problems getting this to shoot 1 MOA consistently.
-z |
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Zak:
Is your barrel chrome-lined? If not, is it something you'd worry about? How effective would the round be out of an 11.5" upper? 14.5? 16? I'm not sure I'd want to put an 18-20" upper on a rifle I'd plan to use for home defense. Or should I stick with 5.56mm in a 14.5" or 16" upper for home defense, since the rounds will fragment more readily? Is anyone producing 6.8mm compatible suppressors for the civilian market? |
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No, it's stainless, just like the majority of my AR15 barrels (4 of, uh, 5 or 6) because I want the additional accuracy and I shoot mostly 75gr bullets at < 2750fps (in 223). I'm also not slogging through swamps, which probably helps.
The standard "short" 6.8 barrel length is 12". Here's what you can expect with factory ammo: 18": 2700 - 2800fps 16": 2650fps 12": 2400 Who knows about "effective" ? Based on the performance of other OTM bullets (75-77gr), we should expect the 115gr OTMs to perform down to 1800-2000fps, but this is just my conservative guess. A 110gr VMAX ought to fragment at even lower speed. From similar barrel lengths, I would expect the 6.8 to have better terminal ballistics than 5.56, besides armor. If you want a 6.8 can, contact Gemtech. Alternatively, just use any 308 can. -z |
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There is an article in the Guns and Ammo "Book of the AR15" (which is on the magazine stands now). I don't know anything about the author(Gary Paul Johnston) or the veracity of his statements, but here are some things he mentioned:
He tested 4 different guns, 2 16.5" and one 18.5" (bolt groups and uppers made by LMT) and a CZ bolt gun. Ammo was some handloaded and some early production from Remington. He stated all ARs gave around 1 moa with range from 1.31 to .53 inches @ 100 yards (I am assuming 3 round groups). The MV ran from 2621fps for 16.5 to 2714 fps for 18.5. The cz as running 110 gr Vmax and the took a mule deer buck from 75 yards. 22 inch barrel with 2791fps MV with less than 1MOA. Seems like the magazine has a lot of good information and articles, but I am not 'in the know' so I can't comment of the accuracy of the information. |
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I am really happy with my 6.5 Grendel, I get the extra power and can shoot out to 1000yrds. and its here now. Its ballistics are right with the 7.62 NATO.
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A 12" 6.8 AR will be fragmenting out to 75-100m, which is a huge improvement over .223, and it does more damage at all ranges.
-Troy |
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i can't wait until someone produces cheaper 6.8 barrels...
once i can get a 6.8 SS barrel for around $200... buy an LMT upper $125... buy a bolt $who knows... i'm in bussiness... bring on the ammo remmington.. bring on the barrels ABC-R! my new tactical deer rifle |
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When I see the ammo sitting on a store shelf, then I will believe.
Preferrably before deer season |
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When I see fruitballs from this site BUMPFIRING IT, I'll believe.
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My take on that caliber as a CIVILLIAN is that I do not have and may never be able to legally acuire the correct hi cap magazines for the 6.8, I cannot get limitless quantities of cheap ammo, and it will take several years and good political fortune before I can.
What I can do, if i have to, is get a platform that is close : 7.62 x 39. The drawback for the AR platform is that the AK magazines don't work, and they are the proper geometry the round requires to reliabley feed high caps. So you are left with either an AK platform, or perhaps a Robinson Armament platform that takes AK mags - and I don't know if those are available to us civies. For me, I've been thinking about a Galil AR clone in 7.62x39, or maybe a Micro Galil in that cal by Vulcan Armament after the ban passes so their stocks will fold. |
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I am certainly no expert on this, but from what I understand, the 7.62x39 has no where near the performance qualities of 5.56 MUCH LESS 6.8.
Also, I don't see how getting magazines for this are a problem. As long as the AWB sunsets, there should be no problem with availability. Even if (god forbid) the ban didn't sunset, you can replace some old 5.56 mags with replacement bodies. I think the problem with the foreseeable future is that the cost per round may not go down. Which would make this a more expensive prospect. If that were the case, then I would seriously consider getting into reloading my own. |
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Hmm. I'll have to contact Gemtech and ask about using a .308 can. I'd love to be able to swap the same can between the 6.8mm SPCs I plan to build and the 7.62mm FAL I plan to build. :) So many plans, so little money! |
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MSTN is the source for the PRI magazine body coversion kits which allow you to "rebuild" your existing 30-round AR15 magazines to be 6.8-compatible. The ban is sunsetting in about a month, so rebuilds will be a moot point after the sunset. A lot of shooters here have a distorted view of ammo prices: they are used to buying "new" ammo for dirty cheap. This is only possible in two or three rifle calibers (5.45, 5.56, and 7.62x39) because most of the world's militarys use them. The price for new 6.8 SPC ammo will be in-line with "match" 308 ammo from Black Hills. If you want to shoot 6.8 for the same price as you blast 223 ammo, get yourself a Dillon 650 or 1050 and start cranking. -z |
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Here's a cost breakdown for reloading 6.8SPC. We may not be able to reach the ballistics of the factory 115 because they have special noncommercial powders.
Assume $210/1000 cases from the first batch of brass, and that you can reload each case 5x before you lose it or it stretches too much. (conservative). That's 4.2c/firing. Primers are about 1.6c/firing, powder will be about 6.3c per, and bullets are between 9 and 18c per. That comes to about $300 per 1000 reloaded... This is cheaper than you can buy 75gr Black Hills 223 (blue box) for. -z |
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This makes no sense. The 6.8SPC has a trajectory essentially identical to 75-77gr 5.56 or 150-168gr 308WIN.
The 6.8 numbers used there are ones I from my handloads (110gr) or from the preproduction 115gr, so are a little less than you'd expect from the real production ammo. Also, the 223 and 308 numbers are from 20" barrels, while my 6.8 numbers are from a 18" barrel. -z |
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DO FOLKS INSIST THEIR 7.62X51 BARRELS ARE CHROME LINED? NO. WHY? NOT A REQUIREMENT AT 7.62X51 VELOCITIES, WHICH ARE QUITE SIMILAR TO THAT OF THE 6.8 SPC.
ALSO, OUR 6.8 SPC MATCH-GRADE STAINLESS STEEL BARRELS ARE FAR MORE CORROSION RESISTANT THAN ANY CHROME MOLY STEEL BARREL WOULD BE UNLESS OF COURSE HARD CHROMED. AND FRANK WHITE OF COMPASS LAKE DOES A GREAT JOB ON THE CHAMBERING OF THESE STAINLESS BARRELS, SO I DO NOT ANTICIPATE EXTRACTION WILL EVER BE AN ISSUE WITH A PROPERLY MAINTAINED WEAPON. WES GRANT M.S.T.N. |
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Perhaps if the Mil ever does anything significant with this round Chrome lined barrels will start to be produced. Like I said before, I won't mess with this round until its been a mainstream Military round for AT LEAST 10 years.
I only have one .308, and it's not chrome lined. Copper fouling is a major pain in the ASS with that gun. |
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Military purchasing authorities will NOT be buying the 6.8 SPC cartridge, and those who need to know have been informed. Thus, it looks like the 6.8 SPC is solely a commercial, civilian round.
John ---------------- 6.5 Grendel: AR10 Soul in an AR15 Body www.65grendel.com |
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That's a good way to put it. Though any BH blue box costs me approximately $255 per thousand shipped. I'm looking harder and harder at buying a 6.8 barrel and bolt for another build |
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I've read now in 2 different threads that the military is canning this round. Can anyone give any insight as to why they are not going to proceed with this?
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There's more to the story than merely matters of technical performance, which I have ideas on but won't speculate here. The powers that be obviously know all the reasons, and it'll be interesting if anyone makes a public statement.
However, though we know the 6.8 SPC is a decent round, it did fail the FBI's suite of pistol-caliber tests. It had trouble with intermediate barriers, although, of course, that's largely a function of bullet construction. John ---------------- 6.5 Grendel: AR10 Soul in an AR15 Body www.65grendel.com |
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Grendelizor,
WOW, this is the first I've heard that the 6.8 has been deep-sixed by the US military. Are you sure? Man, I've never seen the sort of positive buzz and excitement (on the internet, in the gun rags, etc) like the news of USSOCOM testing the 6.8 cartridge has generated in the past year...it just seems really surprising to me that it's been dropped completely. Anyone else have any info on this? Will |
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Grendelizor,
Have any good news about 6.5 Grendel, or have they ditched alternative-caliber AR15 uppers altogether? -z |
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Zak, no news about widespread adoption of the 6.5 Grendel. However, good news about its performance this week in the FBI protocols. In the words of my source, the 6.5 Grendel "stormed through" the FBI tests and "destroyed everything in front of it" and the audience "absolutely loved it." I will post separately later, but you'll be disappointed because the sponsors refuse to release any of the photos or videos of the gel blocks. My notes will be sketchy, at best.
It seems that, in the short term, the military is mostly interested in intermediate cartridges in the DMR role. To get widespread adoption is to turn a very big ship with a very small rudder. My end game is to see SOME kind of intermediate cartridge adopted as a universal round replacing both the 5.56 and 7.62 for assault rifles, light and medium machine guns, and light sniper rigs. I wouldn't have been super-traumatized if it had been the 6.8 SPC because it really is a good effort, although you know all along I've said I consider it a distant second to the 6.5 Grendel. In the meantime, I have to maintain that the 6.5 Grendel stands on its own merits, whether its adopted or not. People certainly like hunting with the 6.5 caliber, the Army Marksmanship Unit has it, and one guy even got his Grendel in time to rush it to the Camp Perry competition. John -------------------- 6.5 Grendel: AR10 Soul in an AR15 Body www.65grendel.com |
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No offense to you, but that makes me suspicious. I have yet to see a 6.5mm bullet that will meet the FBI and IWBA specs with regard to where in the wound channel it fragments. All of them so far have taken FAR too long to begin yawing/fragmenting...which is what makes it such a good bullet for large game. Granted, I haven't seen them all, but... If they want to brag on this as a weapons platform, they better start showing it off. Until then, I'll consider it to be an excellent hunting/target round, but nowhere near as effective as the 6.8 in terminal performance. |
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Brouhaha, no offense taken. You're disappointed, I'm disappointed, but such is the nature of these things. Any truly serious testing program by authorized agencies is not going to have their results plastered all over the internet for general consumption.
You're probably right about the fragmentation characteristics. In most tests the yaw was fully developed between 5 and 7 inches. In "Test Event 6: Automobile Glass" the yaw was fully developed at about the 3-4" mark. It should be noted that they were firing a 144-grain Lapua FMJBT, because that's what the sponsors wanted. They are "hyper" sensitive about any bullet being in any way interpreted as a hollow-point by international law. John ------------------- 6.5 Grendel: AR10 Soul in an AR15 Body www.65grendel.com |
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Zak, I don't know the velocity from an 18". They were shooting 18.5" and 24" at these tests. Alexander Arms has created 16" prototypes, but are not currently manufacturing them. Did you try calling Bill Alexander at Alexander Arms for velocity of something around 18"? He's got a website (if you can call it that! hn
-------------------- 6.5 Grendel: AR10 Soul in an AR15 Body www.65grendel.com |
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Agreed on that. However, I have yet to see ANY gel photos from the 6.5G. Surely by now some independent testing would have been done or some leaked photos would have gotten out. Something.
Yeah, 5" is pretty far and 7" is much worse. 4" isn't absolutely horrid, but I'd like to see 1-1.5". I wonder how a 140gr SST or Amax would perform. |
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Brouhaha, believe me, I've been hoping, praying, begging for leaked photos. Nothing doing.
Alexander Arms has a factory load with a 129gr Hornady SST, which should be just as interesting, if not more so, than the 140. John ------------------- 6.5 Grendel: AR10 Soul in an AR15 Body www.65grendel.com |
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Are we going to see MRP barrels for 6.5 Grendel ever? I keep bugging LMT about 6.8 barrels.
It's a lot more compelling to drop in a $350 barrel than to build a whole new upper. -z |
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BTW - had a friend with a Rem LE rep ask about ammo, about a week ago. They were still planning to ship to distributors this month or early next.
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That is the same I have seen published. All reviews are saying the 6.8 SPC is shooting 1.0 MOA at 100 yards. On the other hand we have the 6.5 Grendel which is shooting much better at 0.5 MOA at 600 yards! According to Arne, the Army Marksmanship Team bought several 6.5 Grendels and there are also 6.5 Grendels currently being used downrange in Iraq. If the 6.5 Grendel gets used enough as an alternative round by our SOCOM guys it could eventually be considered as a 7.62 and 5.56 replacement through "proof in action." |
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Isn't that how the AR15 became the M16, through the "back door" in the early days of VietNam? |
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6.5 Grendel in Iraq that is news to me, I did not think it has a JAG approval as of yet. (maybe I am wrong here). As far as I know the 6.8 has not been used in theatre in combat as of yet, I guess we shall see. I'd like to see some of the ballistic data on the 6.5 and case dimensions, I am curious. When the 6.5 SPC was shot in gelatin the results were not that great. It had good velocity and good accuracy but it lacked good terminal effects, a little better than the 77gn 5.56mm. If your bullet doesn't upset (yaw) until 4-5" in gelatin what difference is it to an 62gn 5.56mm M855 bullet (Other than diameter and maybe so temporary cavity effects). So I am kind of curious here.
My key questions for 6.5 Grendel likers are (please don't take offense here: I am genuinely curious): How many rounds in a magazine? Are the terminal effects better than a 5.56mm 77gn bullet? How much recoil, muzzle flash, noise and muzzle rise in comparison to a 6.8 in semi, burst and full auto. What is the pressure like in the chamber-is it more than the 6.8? and if so what effect does it have on short barreled, gas operated guns (ala. the M-4) and also at mass production rates. Not the finely tuned custom product- I am talking about average Q.C. here. How much do terminal effects and muzzle velocity suffer when you go from a 20" to a 16.5", 12" or a 10" been kind of curious there, I know what the 6.8 and the 5.56mm do. How long is carrier dwell time in comparison to an 5.56mm M-4, and what is bolt carrier velocity on the rearward and forward stoke. I have heard it has the edge in velocity and possibly in accuracy at distances over 500M. What need is there in a combat rifle that most of the services (with the exception of the Marine Corps) can't shoot accuratly over 300M (and even that distance is a hope for many in uniform). What is the 6.5 Grendel trying to replace? the 5.56mm? or the 7.62mm? or both? The 6.8 is meant only to replace the 5.56mm (contrary to some belief). Like, I said I am curious here just want to know. |
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I expect that Combat_Diver will report back with results after it is issued to him. Possibly some anecdotal evidence of its terminal effectiveness.
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The 6.5 guys are talking about max pressure below 50,000psi, closer to 45,000 psi. I think 6.8 is running at a max of 55,000psi. With a mid-length gas system and the right port size, dwell time and bolt speed should be no problem. My MSTN/PRI 6.8SPC upper runs perfectly.
-z |
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PAUL HAS AN UPPER WITH STRAIN GAUGES AND WIRES ALL OVER IT, HOOKED UP TO HIS COMPUTER, THAT HE USES FOR LOAD DEVELOPMENT. THE 6.8 SPC IS A MILD 49,000 CUP.
THE 6.8 SPC IS OPTIMIZED IN THE 16" BARREL, YET WILL PERFORM WELL IN BARRELS AS SHORT AS 12". WES |
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Autobahndriver wrote: "There are also 6.5 Grendels currently being used downrange in Iraq."
OK, I can see the rumor mill is getting a little overheated. The 6.5 Grendel has been to Iraq, but I wouldn't characterize the situation as "currently being used downrange." There is still much more testing to be done. (By the way, did you hear the 6.5 Grendel ripped through the FBI gel-test protocols? Not even the 6.8 SPC passed them all.) KMFDM has some questions and I'll try answer only the few that I can: "How many rounds in a magazine?" How many would you like? Seriously, they've got the civvie 10-rounder, a 17-rounder of the same external size as a 5.56 20-rounder (holds 18, but spring reliability is better with 17), and a 25-rounder the same external size as a 5.56 30-rounder. "Are the terminal effects better than a 5.56mm 77gn bullet?" Yes, if you call splitting an 8-inch gel block from top to bottom better. The 6.5 Grendel recently underwent terminal testing according to the standard FBI protocols. However, none of us will see the sponsoring party's results, so we won't be able to armchair analyze its terminal effects in detail. The military knows what it can do. If you're authorized, I'm sure you can get the results. If one isn't in the military, then you're using hunting bullets, and we've got 100 years and counting of knowing what 6.5 hunting bullets can do. Another word on terminal effects. Gel-testing only replicates performance in the human body to something like 64%. So it gives only an indication, but nothing ever definitive. And there is no "magic" bullet. Again, we've got 100 years of shooting things with 6.5 caliber bullets. So there's nothing mysterious about the caliber; ask Scandinavian moose, they know it well. Within the caliber, we can make any bullet you like. You want fragments? We got fragments! You want armor-piercing? We got AP. The fact that a 30-year-old standard FMJBT 144gr Lapua bullet is ripping gel-blocks apart is a good sign, but that's only a start. The recent testers wouldn't even touch the 123gr Lapua Scenar OTM because its fragmentation might be even more aggressive than any OTM we currently use (this is a match round only and soley to balance the weight for accuracy is there a hollow cavity in the nose; sort of like the Russian 5.45 round). "What is the pressure like in the chamber-is it more than the 6.8?" The 6.5 Grendel factory ammo runs pressures of 48,000-49,000, as tested over six pressure barrels. "What is the 6.5 Grendel trying to replace? the 5.56mm? or the 7.62mm? or both?" It's mainly aimed at giving 7.62 capabilities in a lighter, more compact package. I, personally, would argue that it be a multipurpose cartridge to replace both 7.62 and 5.56 in assault rifles, light and medium machine guns, and light sniper rigs. But there's a huge concern in the military over the weight of the ammo load, so 5.56 looks to stay in the near term. But then they develop the doctrine of the "double-tap" and they use up 5.56 rounds at a faster rate anyway! Two 62-grain chunks of lead or one 123- or 144-grain 6.5 Grendel chunk of lead: What's the difference? Anyway, don't get me started on that. . . . John ----------------- 6.5 Grendel: AR10 Soul in an AR15 Body www.65grendel.com |
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