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 20 inch barrel vs. 24 inch barrel:
LARRYG  [Team Member]
6/27/2007 9:50:39 PM
Okay, here is the question:

With all other factors being the same such as manufacturer of the round, bullet weight, quality of the barrel, profile of the barrel, twist rate, everything being the same, what could I expect in terms of accuracy, muzzle velocity, and range between the two barrels? Let's say the target is a 6 foot tall, 3 foot wide rectangle, just for giggles and grins.

I specifically ask about .308/7.62 NATO. I am talking about quality ammo (the same in both rifles) and quality barrels, the same in both rifles except the length.

As an aside, is a quality heavy stainless barrel of the same quality, length, and profile of a heavy chrome moly barrel like you see on most bolt guns going to be more accurate? Again, barrel profile and, in this case, length would all be the same.

Lawman734  [Team Member]
6/27/2007 10:11:10 PM

Originally Posted By LARRYG:
Okay, here is the question:

With all other factors being the same such as manufacturer of the round, bullet weight, quality of the barrel, profile of the barrel, twist rate, everything being the same, what could I expect in terms of accuracy, muzzle velocity, and range between the two barrels? Let's say the target is a 6 foot tall, 3 foot wide rectangle, just for giggles and grins.

When I had my Mk11 Mod0 (20" bbl), a 6'x3' target would be fair game out to a 1000yds. I've used it at the Hardrock match in AL 2x with good results. You never said anything about terminal velocity, so I won't go there. With that said, the 24" barrel will give you about 100fps velocity increase (using the old rule of thumb of 25fps per inch), which means less wind drift and drop.

I specifically ask about .308/7.62 NATO. I am talking about quality ammo (the same in both rifles) and quality barrels, the same in both rifles except the length.

As an aside, is a quality heavy stainless barrel of the same quality, length, and profile of a heavy chrome moly barrel like you see on most bolt guns going to be more accurate? Again, barrel profile and, in this case, length would all be the same.

You won't find much of a difference in accuracy as much as the SS supposedly has a longer barrel life. Since the .308 is hardly considered a barrel burner, I don't think it really matters.

LARRYG  [Team Member]
6/28/2007 2:48:53 PM

Originally Posted By Lawman734:

Originally Posted By LARRYG:
Okay, here is the question:

With all other factors being the same such as manufacturer of the round, bullet weight, quality of the barrel, profile of the barrel, twist rate, everything being the same, what could I expect in terms of accuracy, muzzle velocity, and range between the two barrels? Let's say the target is a 6 foot tall, 3 foot wide rectangle, just for giggles and grins.

When I had my Mk11 Mod0 (20" bbl), a 6'x3' target would be fair game out to a 1000yds. I've used it at the Hardrock match in AL 2x with good results. You never said anything about terminal velocity, so I won't go there. With that said, the 24" barrel will give you about 100fps velocity increase (using the old rule of thumb of 25fps per inch), which means less wind drift and drop.

I specifically ask about .308/7.62 NATO. I am talking about quality ammo (the same in both rifles) and quality barrels, the same in both rifles except the length.

As an aside, is a quality heavy stainless barrel of the same quality, length, and profile of a heavy chrome moly barrel like you see on most bolt guns going to be more accurate? Again, barrel profile and, in this case, length would all be the same.

You won't find much of a difference in accuracy as much as the SS supposedly has a longer barrel life. Since the .308 is hardly considered a barrel burner, I don't think it really matters.



Thank you sir. Not being that familiar with the Mk11 Mod0, I seem to recall they have a 20 inch barrel, correct? So, I take it you are saying that either would be good on a 6x3 target at a 1000 yards. Correct?
Lawman734  [Team Member]
6/28/2007 3:03:28 PM

Originally Posted By LARRYG:

Thank you sir. Not being that familiar with the Mk11 Mod0, I seem to recall they have a 20 inch barrel, correct? So, I take it you are saying that either would be good on a 6x3 target at a 1000 yards. Correct?


Yeah, the Mk11 has a 20" barrel. Both will work, one better than the other because it does give you more velocity-but it can be done. You'll need handloads to get that far with a 20" barrel as most factory loadings won't give you the velocity.
I'd personally opt for a 22", you get to lob off 2" and still get a little more velocity than the 20"bbl. When it comes to shooting the .308 at 1000yds (hell, anything that far), the more speed the better.
Tactical_T  [Team Member]
6/28/2007 3:04:41 PM
Knights SR-25 MK 11 MOD 0 Navy Rifle

She's crazy expensive and totally unavailable to the "civilian" market, just like all their other battle rifles. Next best 20" semi-auto sniper rifle is probably the Armalite SuperSASS. I "think" they both have a 1:10 twist, which is probably ideal for a 20" barrel .308 where you wanna use 168g BTHP match ammo. I'd think that both rifles are probably good for man-size targets out to 1,000 and "consistantly" accurate out to about 600. Hopefully we can see a side-by-side evaluation in the future.

Knight's