Small Arms Caliber Debate

Status
Not open for further replies.
Originally Posted By: hatt
Originally Posted By: OVERKILL


Great article. Sounds like most guys prefer the .308 and that it was/is a significantly more effective cartridge. The issue is the recoil, which leads to slower follow-up shots. I'm sure that could be dealt with, at least in part, by an improved chassis designed to reduce felt recoil, if one were looking at a new rifle to work with an existing (or, as per the article, "battle proven") cartridge.

The weight and bulk of a 7.62 platform and ammo over 5.56 is significant. Soldiers these days are humping a lot of gear. 7.62/.308 is out and never to return for the average soldier.


Ammo, yes, definitely. .308 is heavier and takes up more space (so you can carry less of it). However having handled both a Colt AR-15 and the Robinson XCR in .308, there really isn't much of a weight difference between the two rifles.
 
Originally Posted By: hatt
Originally Posted By: OVERKILL


Great article. Sounds like most guys prefer the .308 and that it was/is a significantly more effective cartridge. The issue is the recoil, which leads to slower follow-up shots. I'm sure that could be dealt with, at least in part, by an improved chassis designed to reduce felt recoil, if one were looking at a new rifle to work with an existing (or, as per the article, "battle proven") cartridge.

The weight and bulk of a 7.62 platform and ammo over 5.56 is significant. Soldiers these days are humping a lot of gear. 7.62/.308 is out and never to return for the average soldier.


I just looked it up:

The M-16 weighs 7.18lbs empty, 8.79 loaded.
The Robinson XCR .308 weighs 7.5lbs (does not spec loaded or unloaded)
The Colt AR-15 weighs 7.3lbs

So my observation was correct, there really was next to no difference in weight between the two rifles. It is the extra bulk and weight of the ammo that is the primary issue as well as the difference in usability of the cartridge with increased recoil, which I touched on earlier.
 
Originally Posted By: OVERKILL
Originally Posted By: hatt
Originally Posted By: OVERKILL


Great article. Sounds like most guys prefer the .308 and that it was/is a significantly more effective cartridge. The issue is the recoil, which leads to slower follow-up shots. I'm sure that could be dealt with, at least in part, by an improved chassis designed to reduce felt recoil, if one were looking at a new rifle to work with an existing (or, as per the article, "battle proven") cartridge.

The weight and bulk of a 7.62 platform and ammo over 5.56 is significant. Soldiers these days are humping a lot of gear. 7.62/.308 is out and never to return for the average soldier.


Ammo, yes, definitely. .308 is heavier and takes up more space (so you can carry less of it). However having handled both a Colt AR-15 and the Robinson XCR in .308, there really isn't much of a weight difference between the two rifles.

There are a lot of different configs to consider. In similarly configured guns the .223 version is always going to come out lighter. M16A2 and standard XCR-L are under 8lbs. The standard XCR-M is over 9. If you start cutting too much barrel off the .308 to save weight and increase maneuverability you start removing the reason you had it in the first place.
 
Originally Posted By: OVERKILL
Originally Posted By: hatt
Originally Posted By: OVERKILL


Great article. Sounds like most guys prefer the .308 and that it was/is a significantly more effective cartridge. The issue is the recoil, which leads to slower follow-up shots. I'm sure that could be dealt with, at least in part, by an improved chassis designed to reduce felt recoil, if one were looking at a new rifle to work with an existing (or, as per the article, "battle proven") cartridge.

The weight and bulk of a 7.62 platform and ammo over 5.56 is significant. Soldiers these days are humping a lot of gear. 7.62/.308 is out and never to return for the average soldier.


I just looked it up:

The M-16 weighs 7.18lbs empty, 8.79 loaded.
The Robinson XCR .308 weighs 7.5lbs (does not spec loaded or unloaded)
The Colt AR-15 weighs 7.3lbs

So my observation was correct, there really was next to no difference in weight between the two rifles. It is the extra bulk and weight of the ammo that is the primary issue as well as the difference in usability of the cartridge with increased recoil, which I touched on earlier.
Post the link showing the .308 XCR weighing 7.5? That's the .223.
 
Originally Posted By: Shannow
SLR L1A1 in Oz weighed 10lb 15Oz...big difference there.


Yeah the old battle rifles that the original AR15 competed against in the 1950's and 60's weigh a ton in comparison. The AR was also lighter back then having the pencil barrel. The FAL based rifles and the M14 were old school wood and steel versus polymer and aircraft aluminum. The HK91 and CETME guns using stamped steel were the closest thing to lightweight the west really had to offer.

Nowadays the use of alloy and polymer is prolific. But when Eugene Stoner got the idea, it was RADICAL.

I have an old school Colt SP1 (closest to the original M16 you can get) and a Brazillian/Austrian metric FAL kit build. I love both but I will say the FAL gives you a real feeling of substance when you shoulder and fire it. I plan on adding a PTR91 rifle (hk clone) someday to the collection.
 
Last edited:
Is this true?
European NATO countries wanted what is now the 7MM-08, but USA for $$ reasons insisted on keeping .308,
the same caliber as 30-06 and the 30-40 Craig before that.

Sweden 120 years ago developed the 6.5X55, that retained the effectiveness of larger calibers in a much lighter round.

The 6.5mm (.264") bullet has finally come full circle and back in vogue.
Would the .260 Rem, with a 1 in 7" twist be a fix?
 
Originally Posted By: hatt
Originally Posted By: OVERKILL
Originally Posted By: hatt
Originally Posted By: OVERKILL


Great article. Sounds like most guys prefer the .308 and that it was/is a significantly more effective cartridge. The issue is the recoil, which leads to slower follow-up shots. I'm sure that could be dealt with, at least in part, by an improved chassis designed to reduce felt recoil, if one were looking at a new rifle to work with an existing (or, as per the article, "battle proven") cartridge.

The weight and bulk of a 7.62 platform and ammo over 5.56 is significant. Soldiers these days are humping a lot of gear. 7.62/.308 is out and never to return for the average soldier.


I just looked it up:

The M-16 weighs 7.18lbs empty, 8.79 loaded.
The Robinson XCR .308 weighs 7.5lbs (does not spec loaded or unloaded)
The Colt AR-15 weighs 7.3lbs

So my observation was correct, there really was next to no difference in weight between the two rifles. It is the extra bulk and weight of the ammo that is the primary issue as well as the difference in usability of the cartridge with increased recoil, which I touched on earlier.
Post the link showing the .308 XCR weighing 7.5? That's the .223.


Their site only lists one weight for all calibres:

http://xcr.robarm.com/xcrl.php#specs

EDIT, I just derp'd, I was looking at 7.62x39 :facepalm:
 
Originally Posted By: hatt
Originally Posted By: OVERKILL
Originally Posted By: hatt
Originally Posted By: OVERKILL


Great article. Sounds like most guys prefer the .308 and that it was/is a significantly more effective cartridge. The issue is the recoil, which leads to slower follow-up shots. I'm sure that could be dealt with, at least in part, by an improved chassis designed to reduce felt recoil, if one were looking at a new rifle to work with an existing (or, as per the article, "battle proven") cartridge.

The weight and bulk of a 7.62 platform and ammo over 5.56 is significant. Soldiers these days are humping a lot of gear. 7.62/.308 is out and never to return for the average soldier.


Ammo, yes, definitely. .308 is heavier and takes up more space (so you can carry less of it). However having handled both a Colt AR-15 and the Robinson XCR in .308, there really isn't much of a weight difference between the two rifles.

There are a lot of different configs to consider. In similarly configured guns the .223 version is always going to come out lighter. M16A2 and standard XCR-L are under 8lbs. The standard XCR-M is over 9. If you start cutting too much barrel off the .308 to save weight and increase maneuverability you start removing the reason you had it in the first place.


The M14 is 9.1lbs, 10.1lbs loaded. It is heavier than the M-16 but not as much heavier as I expected at roughly 2lbs. Would you describe that as significant or not? Just trying to get a feel as to what sort of weight difference you feel is an issue.

So the XCR-M, in .308, there's the Mini version, which shows a weight of 8.2lbs (but of course doesn't say which barrel that's with). What are your thoughts on this with the 18.6" barrel? I realize it is still going to be heavier than the .223, but would be lighter than the standard XCR-M and I assume the M-14, no?
 
Originally Posted By: hatt
Originally Posted By: OVERKILL


Their site only lists one weight for all calibres:

http://xcr.robarm.com/xcrl.php#specs

Here's the .308 versions: http://xcr.robarm.com/xcrm.php


Yeah, see my edit above, I realized I screwed up when I went back and checked after you took issue with it, LOL!
blush.gif


The one I've handled was a standard XCR-M in .308. Was actually thinking of picking one up but then I blew too much money on the Lapua
grin.gif
 
Originally Posted By: OVERKILL


The M14 is 9.1lbs, 10.1lbs loaded. It is heavier than the M-16 but not as much heavier as I expected at roughly 2lbs. Would you describe that as significant or no? Just trying to get a feel as to what sort of weight difference you feel is an issue.
I don't think it's heavy. I'm not going to tote it all day. For people that do. 1-2 lbs, plus heavier bulkier ammo, plus heavier bulkier mags, might be a different story.
 
Originally Posted By: hatt
Originally Posted By: OVERKILL


The M14 is 9.1lbs, 10.1lbs loaded. It is heavier than the M-16 but not as much heavier as I expected at roughly 2lbs. Would you describe that as significant or no? Just trying to get a feel as to what sort of weight difference you feel is an issue.
I don't think it's heavy. I'm not going to tote it all day. For people that do. 1-2 lbs, plus heavier bulkier ammo, plus heavier bulkier mags, might be a different story.


Yeah, I think, as I mentioned earlier, that the heavier, bulkier mags and ammo are probably the bigger issue of the two. I can carry around my .308 pretty easily (and it is a fair bit heavier than the guns we are discussing) but carting around the ammo, if I'm going to shoot a lot, you can really feel the weight.
 
Originally Posted By: userfriendly
Is this true?
European NATO countries wanted what is now the 7MM-08, but USA for $$ reasons insisted on keeping .308,
the same caliber as 30-06 and the 30-40 Craig before that.

Sweden 120 years ago developed the 6.5X55, that retained the effectiveness of larger calibers in a much lighter round.

The 6.5mm (.264") bullet has finally come full circle and back in vogue.
Would the .260 Rem, with a 1 in 7" twist be a fix?


No during the NATO standardization debate/debacle, the Brits were pushing hard for their .280 round which was 7x43mm in metric measurements. It was the middle strength round in early testing against the American T65 cartridge (which became the 7.62x51mm NATO) and the German 8mm Kurz (7.92x33mm). The American delegation insisted that none of the European cartridges had the power and accuracy at long range. Essentially the Europeans were looking at the last war and determined that most fighting was going to be closer than in the old days (300 meters or less) so they thought the Brit round was a good balance. The Americans were looking for something that could be more compact than the old 30-06/30M2 but have similar performance.

Well the British round was out then...and their platform, the EM2 bullpup could not adequately be "beefed up" to take the punishment of the American round. The Belgian design, however could and the Brits and Americans who ran the show with NATO standardization made a deal. The NATO round would be the American round if the Americans agreed to adopt the FAL. Well, we had a sudden case of "Buy American" and went back on our word. Nato standardization then went all sorts of sideways and was watered down from the original goal of near universal equipment standardization.
 
Last edited:
Lots of guessing here. I shoot weekly with a retired Army vet of the sandbox. Of the small arms available the M4 was the weapon of choice for the Army teams he was with. Why? Because they wear body armor and fixed stock rifles and shotguns are unusable in this situation. With the stock collapsed it can be used effectively with B/A in the tight spaces of typical homes/buildings there. Why not a handgun? 2 reasons, #1 is that many of the enemy are also wearing body armor and the team is not interested in a stun shot. #2 reason is our guys didn't trust the Beretta. Shotguns were coveted but not widely available, he says the Marines used them more than the Army. Sub-guns were useful but not widely available and wouldn't reliably defeat enemy body armor. Plus they had to be trained specifically for sub-guns. M14s and other large caliber rifles would be deployed for cover to engage runners or enemy trying to get into the fight.

M14s or handguns would not have been the weapon of choice for house clearing. He says the 5.56 round worked just fine in CQB. Take this for what it's worth but it's the experience of a guy who did it.
 
The M14 was reissued largely as a Designated Marksmen Rifle. When the military dropped the 20in full length AR models for the carbine length M4, it really shortened the effective range of the round by chopping 5.5 inches off the barrel. The round was designed to do what it does with a 20 in barrel. The small caliber high velocity concept only works with high velocity or you will just punch small holes in people. This is one reason we saw the use of heaver 5.56 rounds in an effort to regain some performance.

The M14 could really reach out and touch someone. However, it is an animal from a different time and finding armorers competent to work on them in the field as well as parts availability given they have not been made in military form in America since the 60s were serious issues at first, which is why you saw AR10 variants introduced in number as well.
 
Last edited:
just had a brainsnap...it was rumoured that the cartridges being tested at the range were 6x45...
 
Originally Posted By: KJSmith
It has always been my understanding that "killing" was not the primary goal.

A dead soldier is 1 removed from the fight.

A wounded, screaming/crying soldier can remove 3+ from the fight.

If I remember correctly, this was a lesson learned from the Japanese in WW2.



That's correct, but the military need rounds that will cause at least a serious injury at max calibrated range after passing through a flack jacket or kevlar helmet.
In mag terms they have reduced the round dimensions to save weight and allow the air to be filled with rounds in what sometimes seems like rather badly directed fire. So it is a case of the more rounds the better.
 
UltrafanUK, What about the velocity ?

versus a .303 ???

It was like 743m/s, and with the practiced "mad minute"....AND volley fire ?
 
Spray 'n pray.

A 6mm is a baby step from the 5.65, but not a one caliber solution, where as a 25 cal .257 or 6.5mm could double duty.

If Remington rolled out a 25-08 with a 1 in 7."5 twist, the round might have been a commercial success and possibly a military option.
The 1 in 10" twist 260 Rem (6.5-08) was a flop for obvious reasons.

At what distance does bullet flight efficiency trump muzzle velocity?
We are talking non expanding bullets.
Does bullet sectional density trump on target velocity?
 
Last edited:
Status
Not open for further replies.

Similar threads

slo town
My experience 30 floors up during the 1989 Loma Prieta earthquake
2
Replies
20
Views
957
wpod
Nuclear_42
Henry Homesteader 9mm Review
Replies
17
Views
5K
Revving2Redline
clinebarger
Shop Truck build
3 4 5
Replies
83
Views
13K
redhat
W
20,000 miles in a CX-5 GT-R
3 4 5
Replies
91
Views
19K
14Accent
CourierDriver
  • Locked
The internal combustion engines--history
Replies
9
Views
6K
HerrStig
Back
Top