Short v. Long Barrel S308...

[Squidly 0]

Hey gang,

 

I went ahead and bought another S308 this week, just in case some a@#$wipe decides to re-institute the misnomered "Assault Weapons Ban" (and also because it was a convenient excuse). However, the shop only had short barrel S308's in stock - I wanted another long barrel S308 like the one I use now for hunting. I bought it anyway...but I'm wondering if there's any real difference (especially for long shots 175 yds. plus) between these. I know that the long barrel is money from experience....any thoughts on the shorty?

[shaneman153a 39]

accuracy totally sucks, but I'll bail you out and buy it for $100.

[O.S.O.K. 0]

Congrats - you will love the carbine. Truth be told there is probably more difference in accuracy caused by the quality of the individual guns than by the length of the barrels. The shorter barrels are stiffer and should shoot more accurately - given they both have optics aboard. The longer barrel has a longer sight radius and is more accurate when using iron sights.

 

Hope that helps.

[macbeau 902]

For what it's worth - My 16" S-308 will shoot circles around my 21" Argy/Izzy-Imbel-Para-Franken-FAL... Just my experience, putting my best effort into both (Using SA surplus 7.62x51).

 

Macbeau sends...

[appalacious 0]

I've often wondered which is more accurate. Common sense tells me the longer barreled rifle would be more accurate, but according to the guys on here, the carbine is actually a little better. I own 2 21 inchers, but the plan is to sell one and buy a 16 incher, so I'll have both. Then I'll be able to judge better.

 

Incidentally, I just finished my first conversion (nearly- still have to install the trigger guard). That thing basically kicked my ass (G2). But, the perseverance payed off, I like the look. Now if my fbmg's will just show up I'll be set.

 

 

J

[Squidly 0]

I've often wondered which is more accurate. Common sense tells me the longer barreled rifle would be more accurate, but according to the guys on here, the carbine is actually a little better. I own 2 21 inchers, but the plan is to sell one and buy a 16 incher, so I'll have both. Then I'll be able to judge better.

 

Incidentally, I just finished my first conversion (nearly- still have to install the trigger guard). That thing basically kicked my ass (G2). But, the perseverance payed off, I like the look. Now if my fbmg's will just show up I'll be set.

 

 

J

 

Thanks for the replies....interesting that the shorty (16") could potentially be more accurate than the 21" according to the posts. Oh well, yet another excuse to go do some more shooting to find out once and for all! Either way, my Saiga collection is now up to four, and that's a good thing!

[busy_squirrel 1]

Does anyone have the model with the 24" barrel that the owners manual talks about? I havn't seen those ones anywhere.

[Bossman 1]

I`ve had both,the 16" I have now seems to be ever so slightly more accurate than my 21"

I never got a 5 shot group from my 21" that was less than an inch at 100 yds.very close mind you but not once 5 into an inch or less.The 16" I have now has done it many times,not every time but frequently.

Without digging up my notes from the 21" handload experiments I would guess that the difference is no more than 1/4" between the two. The 16" averages 1" @ 100 yds. the 21" averaged 1 1/4" @ 100 yds.

In the realm of semi auto rifles 1 1/4" 5 shot groups at 100 yds. is outstanding.

So whats more important to you? slightly better accuracy or extra velocity?

I`ve decided that the compactness of the 16 makes up for the loss of velocity,and the extra margin of accuracy is a plus.

Bossman

[adamsesq 0]

I`ve had both,the 16" I have now seems to be ever so slightly more accurate than my 21"

I never got a 5 shot group from my 21" that was less than an inch at 100 yds.very close mind you but not once 5 into an inch or less.The 16" I have now has done it many times,not every time but frequently.

Without digging up my notes from the 21" handload experiments I would guess that the difference is no more than 1/4" between the two. The 16" averages 1" @ 100 yds. the 21" averaged 1 1/4" @ 100 yds.

In the realm of semi auto rifles 1 1/4" 5 shot groups at 100 yds. is outstanding.

So whats more important to you? slightly better accuracy or extra velocity?

I`ve decided that the compactness of the 16 makes up for the loss of velocity,and the extra margin of accuracy is a plus.

Bossman

Good info, thanks Bossman. Have you any comparison at 200 yards? I am wondering if your 21 might come "back" into its own in comparison?

 

Also, you mention loss of velocity between the two. Do we have any comparisons for this or chronos anywhere - admittedly I have not searched for this at all.

 

-Scott

[Tokageko 8]

<throws a monkey wrench into the gears> More accurate with what bullets?

 

Barrel length, and thus velocity, may make one rifle more accurate with heavier bullets, and the other more accurate with lighter bullets.

 

Have fun!

[G O B 3,516]

Bullets, temperature of barrel, harmonics of you'r front grip-lots of variables, verry little real world difference.

I like the longer barrel for ergonimics and reduced flash-but the difference is too small to really give too much thought to.

[Bossman 1]

Scott, I dont have any data as far as the velocity loss is concerned,I dont have a chronograph yet. I would imagine that 5" of barrel should make a substantial difference,maybe 100 fps. or more but thats just speculation.

There is a video here that shows a bear shot with a 16" .308 saiga...it was GAME OVER very quickly so I guess the 16" still has lots of ass behind it.

[SOPMOD 254]

There's a difference between inherent accuracy and perceived accuracy and most people don't bother to learn the difference so personal experience is anecdotal for 90% of the shooters out there.

 

The more rigid the barrel the more accurate it is and both diameters being equal the shorter barrel will be more rigid and therefore more accurate.

 

You may sacrifice velocity in the shorter barrel but as long as the barrel imparts one full rotation in the rifling to the bullet before it exits the bore the inherent accuracy will not be disturbed.

 

Perceived accuracy on the other hand is a matter of how well you can aim and shoot a particular rifle.A longer sight radius and a front sight post that is further away from you appearing to be smaller will yeild greater accuracy with iron sights in the hands of novice shooters.Also the slightly greater velocity from some high pressure commercial loads may make bullet drop compensation less of an issue as well thereby adding to the myth of "longer barrel=Greater accuracy".

 

I split the difference and took a 22" model and cut/crowned/threaded the barrel to 17.71" which is what HK and the German Government determined was the optimum efficiency and powder conmsumption for the G3/HK91 rifle.This barrel length supposedly combusts 98% of the powder in German 7.62 NATO ammunition.The fantastic West German military ammunition is the benchmark for milsurp ammo and suits my needs perfectly but using some of the hotter commercial loadings might actually derive some benefit from the 22" barrel but I'm not going to worry about it because mine will be eating a steady diet of surplus and milspec 140-150gr ammo for most of it's existence only using commercial stuff for hunting and the occasional long range shooting attempts.

 

 

In summary:

Barrel length is only relevant for velocity and rigidity

Longer Sight Radius increases perceived accuracy with iron sights

Determine what type of shooting you want to do and pick the right tool for the job.

Why not buy both lengths and take the "Pepsi Challenge" yourself

Edited February 24, 2007 by SOPMOD

[busy_squirrel 1]

Again, they claim to make 3 barrel lengths. Are only 2 lengths imported to the US?

[SOPMOD 254]

Again, they claim to make 3 barrel lengths. Are only 2 lengths imported to the US?

 

 

The primary importer only lists 2 barrel lengths so I imagine you are right.

 

Why in the hell would you want a 24" barrel on something as anemic as a 308 though?

[busy_squirrel 1]

I don't want one, but I'd like to see a picture just once.... GUess I could also use it as a spare barrel while I modify the first one.

[Tokageko 8]

24" is a standard length for match rifles. It allows for two full rotations of the bullet before it exits the barrel (1 in 12 twist, 308 05 30-06). Same reason they went to a 1 in 7 twist for the 14" barrels on M4 carbines. Common wisdom is that the greater the number of rotations the bullet goes through before existing the barrel, without losing velocity, the more accurate it will be at longer ranges. With a full two rotations, you've got better stability than with only one-and-a-half, or less. I'd also like to point out that the accuracy differences between the two barrel lengths will be much more noticable once you are shooting past the 300 yard mark. The drop off in velocity, as well as long range destabilisation*, and the lesser degree of initial stabilisation, the longer barrel always comes out on top.** The important point here is: the accuracy differences are likely to be negligable until that 300 yard mark is reached.

 

 

 

 

*The longer a bullet travels at the right rate of speed for its rotation, the more stable it will be. With a shorter barrel, the velocity starts out lower, and thus the bullet drops out of it's optimal speed range after a shorter period of time.

 

**Assuming the same cartridge loadings were used in otherwise identical rifles.

Edited February 25, 2007 by Tokageko

[Tokageko 8]

Oh, and the 308 NATO* is definately not anemic. ;P

 

 

 

 

 

 

*I say "308 NATO" just to piss of the idiots who think there's a difference.

[SOPMOD 254]

24" is a standard length for match rifles. It allows for two full rotations of the bullet before it exits the barrel (1 in 12 twist, 308 05 30-06). Same reason they went to a 1 in 7 twist for the 14" barrels on M4 carbines. Common wisdom is that the greater the number of rotations the bullet goes through before existing the barrel, without losing velocity, the more accurate it will be at longer ranges. With a full two rotations, you've got better stability than with only one-and-a-half, or less. I'd also like to point out that the accuracy differences between the two barrel lengths will be much more noticable once you are shooting past the 300 yard mark. The drop off in velocity, as well as long range destabilisation*, and the lesser degree of initial stabilisation, the longer barrel always comes out on top.** The important point here is: the accuracy differences are likely to be negligable until that 300 yard mark is reached.

 

 

 

 

*The longer a bullet travels at the right rate of speed for its rotation, the more stable it will be. With a shorter barrel, the velocity starts out lower, and thus the bullet drops out of it's optimal speed range after a shorter period of time.

 

**Assuming the same cartridge loadings were used in otherwise identical rifles.

 

 

Without an exponential increase in barrel diameter nothing you said is even possible due to a lack of regidity and bad barrel harmonics.

 

MOA is MOA whether it is out of an Encore with a 10" barrel or a Remington PSS with a long barrel and the fact that the USMC is testing 16" sniper rifles with only velocity loss impeding their adoption I really can't completely agree with anything you just posted in any practical(portable) barrel contour.

 

I have a 338 Lapua with a 29" barrel and it is massively thick to obtain the same rigidity accracy as my little 308 Remington LTR with a much shorter,thinner barrel.The shorter rifle can be thinner because it is more rigid than the 29" 338.

 

ie if you wanted a 24" Saiga 308 it would need to be an inch in diameter at the muzzle to produce identical accuracy to the 16" each using their favorite loading.

 

Rigidity/Harmonics are the critical issue not length

[SOPMOD 254]

Oh, and the 308 NATO* is definately not anemic. ;P

 

 

 

 

 

 

*I say "308 NATO" just to piss of the idiots who think there's a difference.

 

Where do you get your information? A role playing or video game

 

If you own a chronograph you can see the extra 200FPS generated by a commercial 308 load vs milsurp stuff of the same weight and not to mention the fact that acceptable headspace for 7.62 NATO is outside of safe limits for 308 Winchester by winchesters own data!!

 

More shooting and less bullshitting Tokageko

[Tokageko 8]

Greetings - call me americal. The drawings for the 7.62 NATO were used by Winchester to produce the .308. The military has three sets of headspace gauges.One One for match rifles, one for mg's, and one for standard rifles. The chamber is delberately cut a hair larger on the m14 and m1 rifles and MG's to allow for variations in production tolerances among nato countries to ensure compatibility. This information comes from the Rodman Laboratory at RIA from when I was assigned there. In addition, at a later date, I was in charge of the small arms rebuild programs at Anniston army depot and helped FN set up their M240 line in the US. Further I field tested the first XM-21's in Viet Nam and shot competition for quite a few years. At Anniston we compared forster go and no go gauges to production MIL Spec gauges. The no-go was identical. The go for forster was a little tighter than the type II and III gauges we used for standard M14 and M1(.308) rifles and the match gauges for the M21 line where tighter across the board. I have some of the gauges here at home. In attition to the go and no go the military also uses a field gauge - primarily for unit armorors. When a rifle wold close on the no-go it was tested with the field gauge - if the bolt closed on that the rifle was rebarreled. Although the accuracy of those rifles was lower it still met combat conditions. At no time will a rifle who's chamber meets go specs on a mil standard gauge set exceed commercial standards. Note this is not true with 5.56.

 

The Rodman Lab did considerable testing on varying barrel diameters vs accuracy, velocity, and barrel life. This led to the heavier barrel on the m16. There exist thousands of pages of test data on effects of twist rate, bullet shape, bullet density, etc. on accuracy and barrel life on everything from the 1903 onward. The effect of twist rate and bulet velocity are independent of barrel stiffness. The thinner the barrel the more rapidly heat build-up affets accuracy. Note the SVD's long skinny barrel. In my tests accuracy for a ten shot rapid fire string vs an m21 was (given equal quality ammunition) equal for three shots. After that the m21 had the edge. This was because of the barrel harmonics due to rapid heat build up in the svd. Given identical barrel taper and twist rate a barrel length that gives at least two complete bullet rotations will be more accurate than a shorter barrel.

 

Incidently I have fired over a million rounds in match practice and competition (fortunately the army paid the bill) Thanks for your attention - Tokageko's dad. Proud alumni of the 11th Bde, 23d Div, USARV, MAC-C, 196th Bd, etc.

[busy_squirrel 1]

More shooting and less bullshitting...

 

[Tokageko 8]

More shooting and less bullshitting...

 

 

If only the weather permitted... lol

 

Right now my firing range is a pond - in the area between the shooting line and the target boards. Unfortunately, I don't have a suitable set of waders and it's too cold to just hoof it through the water, then stay outside. I guess I'm just not hard-core enough to bring a change of clothes/shoes with me.

[SOPMOD 254]

Greetings - call me americal. The drawings for the 7.62 NATO were used by Winchester to produce the .308. The military has three sets of headspace gauges.One One for match rifles, one for mg's, and one for standard rifles. The chamber is delberately cut a hair larger on the m14 and m1 rifles and MG's to allow for variations in production tolerances among nato countries to ensure compatibility. This information comes from the Rodman Laboratory at RIA from when I was assigned there. In addition, at a later date, I was in charge of the small arms rebuild programs at Anniston army depot and helped FN set up their M240 line in the US. Further I field tested the first XM-21's in Viet Nam and shot competition for quite a few years. At Anniston we compared forster go and no go gauges to production MIL Spec gauges. The no-go was identical. The go for forster was a little tighter than the type II and III gauges we used for standard M14 and M1(.308) rifles and the match gauges for the M21 line where tighter across the board. I have some of the gauges here at home. In attition to the go and no go the military also uses a field gauge - primarily for unit armorors. When a rifle wold close on the no-go it was tested with the field gauge - if the bolt closed on that the rifle was rebarreled. Although the accuracy of those rifles was lower it still met combat conditions. At no time will a rifle who's chamber meets go specs on a mil standard gauge set exceed commercial standards. Note this is not true with 5.56.

 

The Rodman Lab did considerable testing on varying barrel diameters vs accuracy, velocity, and barrel life. This led to the heavier barrel on the m16. There exist thousands of pages of test data on effects of twist rate, bullet shape, bullet density, etc. on accuracy and barrel life on everything from the 1903 onward. The effect of twist rate and bulet velocity are independent of barrel stiffness. The thinner the barrel the more rapidly heat build-up affets accuracy. Note the SVD's long skinny barrel. In my tests accuracy for a ten shot rapid fire string vs an m21 was (given equal quality ammunition) equal for three shots. After that the m21 had the edge. This was because of the barrel harmonics due to rapid heat build up in the svd. Given identical barrel taper and twist rate a barrel length that gives at least two complete bullet rotations will be more accurate than a shorter barrel.

 

Incidently I have fired over a million rounds in match practice and competition (fortunately the army paid the bill) Thanks for your attention - Tokageko's dad. Proud alumni of the 11th Bde, 23d Div, USARV, MAC-C, 196th Bd, etc.

 

 

That's an "ass full" to be sure and despite your impressive resume I have only in the last couple of years found almost none of that barrel harmonics stuff to be accurate and most of the data you are quoting and utilizing is ancient history and if you ask the commercial barrel makers that are now dominating the world of rifle accuracy and making barrels for the military like Lija,Kreiger,Rock Creek,ect they have taken the world of rifle accuracy to a whole new level and what's more they will prove it by producing barrels that are more inherently accurate than anything produced in your service era.The data produced by Rodman also couldn't account for the barrel whip issues in the M60E3 depsite the fact that it met all of the criteria you cite by having sufficient barrel cooling mass in the form of additional length but US Ornance made a barrel 1/3 shorter,with less mass but rigid and hardened to eliminate harmonic issues(and wear) and threw the world of military ordnance testing on it's ear;)

 

The 7.62 NATO headspace issue is with loaded ammunition from all of our NATO allies not the rifles themselves and my Lija barreled Sako headspaced 0.002" on a 308 Winchester SAAMI gauge won't chamber a single round of European Surplus ammunition(port,santa barbara,hirtenberger,ect) so in effect the majority of the world's 7.62 NATO ammuniton is a different measurement(caliber) than US commercial 308 Winchester and if they are supposed to be the same someone might want to tell our allies because they are producing ammuntion sometimes 0.004. over length for our weapons

 

As an item of interest to an old War Horse like yourself I have an M1A DMR built by the team at Lejune in 2003 that utilizes of all things a sleeve that goes over the barrel from the muzzle to the gas tube to forcibly hold the "too skinny" front half of the barrel rigidly in place and it prints sub MOA with the sleeve and opens up to 1.13 without the sleeve and that is the value of rigidity theory in rifle barrels.

 

This same knowledge would have dramatically increased the accuracy of your old M21s and it's funny that the multi-billion dollar Rodman Laboratory couldn't figure that out in 20 years with a billion dollars but a commercial barrel maker that shoots Palma matches needed to tell the USMC how the "cow ate the cabbage"

 

Go check out the test data from the Stewart Wilson USMC rifles at their SWS trials in 2000 and see what happens when Identical rifles(except for barrel length) get tested side by side using modern technology and theory in their manufacture. the shorter more rigid barrels outperformed the longer in every category where velocity and flatness of trajectory were not an issue and that data is right from your own guys

Edited February 25, 2007 by SOPMOD

[Tokageko 8]

"...in every category where velocity and flatness of trajectory were not an issue..."

 

.....

 

ok <shrug>

 

Toka

Edited February 25, 2007 by Tokageko

[Tokageko 8]

Sigh, from tired old americal - greetings. Quite a load to address. Incidently all the xm21's shipped to RVN grouped less than 1" built the old fashioned way. They were all built by the staff of the National Match armorors school at RIA and were individually tested and sitghted in at the Milan rifle club. They let us build a machine rest on their range. The rifle, old fashioned type m14, I took to perry in '76 & '77 shot 1/2 inch groups at 200 yards from a machine rest using a 168 gr. sierra match king and 43.5 grains of 4064. With M118 match it would group at 7/8 in.

 

A lot goes into building an accurate rifle and there are many ways to achieve fine accuracy. Examine a schmit Rubin stock and you will see the two little bumps in the stock channel that provide upward pressure at a selected point. Free floating a heavy barrel works if the barrel is trued to the action and the action face is square. I have used barrels from most of the fine makers in the US. The best bolt gun barrel I ever had was rotary forged at the Rodman Lab and fitted to a pre 64 rifle I also used in RVN (30-06). From a machine rest it would shoot a "0" group at 100 yards - that is to say all the bullets went into the same hole (Lapua d46 185, .309). The rifle was glass bedded and the barrel free floated. I still use an Isaeli mauser .308 that will shoot 1/2 in groups at 100 yards with the above load using the original issue barrel, not bedded, but fittted with a match trigger and issue stock.

 

In short, every way to increase accuracy works for some one.

 

Incidently, as a devoted user of the "pig" the long barrel provided great accuracy. It wasn't too bad to carry (after you dumped the worthless, and heavy bipod) I am curious as to why someone, other than RAMBO, would need or want such a thing. Stand off is the name of the game. Shorter but wider does not seem to lower the weight much. Besides I would have loved the SAW. Incidently, has anyone shortened the 240??? You have not lived until you have had to hump a 1919 - ah sweet memories.

 

Yes, as I stated foreign ammunition caused the headspace to be "loosened" for standard military rifles to ensure compatibility. However not all surplus .308 meets nato specs - for example the extraction cut on S&B and some other ammunition is at a different angle and may require a different shell holder if reloaded. I one owned a mannlicher Steyr Model M in 30-06 that would not chamber any military ammunition. I also owned a Winchester international army match rifle that would only chamber special 300m match ammo from winchester. AS stated chambers can be cut to any tolerance and match/sniper rifles are chambered based upon a specific ammunition type. The current remmington rifles are chambered (for the army) to the LR 175 gr. loading. That does not mean that they wil not shoot other types.

 

I have used rifles with poly. barrels, rotating oval barrels, ligt barrrels , heavy barrels, free floated barrels, hand cut barrels, broached barrels, button rifled barrels, and rotary forged barrels. If the bore is within spec they can all shoot very well with the right ammunition. We used to specify a slight taper from brech to muzzle which seemed to work with the NM m14 and m21 rifles. Hell, the navy even got their .308 converted M1's to shoot good enough for perry. The real important part is the mind behind the trigger. (anemic .308???) - I have seen men shot at over 1000 yards with this ammunition and never heard a single complaint about lack of power from the recipient of the slug. True a .50 is more dramatic - but dead is dead - there are no extra points for a bigger hole. And, If you have ever had to lug a sniper rifle for 25 klicks a day plus 400 rds you will appreciate the difference quickly - especially if you have to hump the radio too. LRRPS live!!! I may be an arthritic ancient but I got great memories. Smile partner!!!

 

Americal

 

------------------------------------------------------------

 

There you have it folks: the source of most of my information.

 

Yes. It's your loveable gun-bunny Tokageko speaking again. I took over the computer again because there was a picture that he wanted me to attach. I was having a hard time finding something to scan with it to show scale, but finally settled on a US dime because it only "almost" covers the group. This is from the aforementioned Israeli converted 7.62 Winchester* 98k, on which not a single number matches. There is, as he said, a match trigger (after-market) in it and it has been scoped, using reproduction German high-turret mounts. I believe the scope is a 3-9x40 Bushnell. Those have been the only modifications, and both of us consider the "receiver flex" created by the thumb-cut to be negligible. Either way, the group is ten shots - made from a bench on a sunny day a summer or two ago, at 100 yards. They are not on a target circle because my father sighted it in approximately 4 inches high - no target turrets and he wanted it sighted for long range shooting.

 

 

Someday, I want to go to a match with that thing and piss off a bunch of people using "pretty rifles." If only I were good enough to hustle them out of some money. (("Betcha $50 I can hit that golf ball...))

 

Either way, I'd like to correct one of my earlier statements regarding progressive destabilisation. As a bullet loses velocity, it is affected more by atmospheric conditions. Yes, your subsequent shots might all end up going to the same place, if the wind is constant across the entire range. You can learn to read the wind, but why handicap yourself with a shorter barrel when trying to make a shot past 300 yards? Again, under 300 yards the difference is non-existant. I'm only talking about long range shooting (defined here as, you guessed it: more than 300 yards). Have I mentioned that 300 yard thing enough?

 

Back to the real topic (I swear I really only wanted to talk about the two models of Saiga 308), lighter match bullets (less than 150 grains or less) may prove more accuracte at longer ranges than heavy match bullets (155 grains or more) when loaded to optimum density (of the poweder inside the case, that is) and fired from a 16" barreled Saiga 308. - That's one of the things I wanted to get across before <-- that theory. I'm also willing to believe that you'll be better off using the heaviest bullets that will stabilize in the 16" barrel, because they will be less affected by wind. That said, the trajectory will probably make shot placement trickier the further out you shoot. If you take that as being true, then a higher initial velocity (as long as the bullet is stabilized) with that same heavier bullet will be easier to hit your target with at greater distances.

 

It's all a matter of comparrison... and oppinion/prefference/etc.

 

Thanks for putting up with me guys!