20 or 24 inch AR-15 Barrel
I'm thinking of buying an AR-15 heavy barreled varmit/target/coyote rifle. Do you guys with AR experience think the 24 in. barrel gives you enough of a velocity/accuracy edge over the 20 in. to warrant the extra weight and cumbersomeness ? I plan on carrying it a few times on coyote/ fox hunts, but I'll probably use it most from the bench and from stationary blinds or whatever!
I put one together
last year to do some prairie dog shootin' and went with the 20" barrel. The longer tube made the rifle muzzle heavy. Not a big deal at the bench, but noticable when you use it as a walk around gun. If I were to do it over again I would spend the extra money on a carbon fiber or fiberglass free-float handguard, as opposed to the aluminum one. JMHO
I have one in .223 with a 20" SS bull BBl and one in .204 with a 23" fluted BBl and both are heavy. There is no accuracy benefit to the 24 inch BBl but there are some down range benefits. If most of your shots will be < 300 yards the 20" will be fine IMO. But the profile and BBl thickness do make either one a tad heavy for a carry rifle. That being said the benefits of having an accurate semi auto, outweigh the downside of a bit of weight, when it comes to a wicked lethal coyote Rig. My .204 is consistantly putting 5 shots into the 4's and low 5's, and that is with cheap midway 34gr dogtown bullets.
RRAs Coyote upper
Hey bro I have a Coyote RRAs upper its a Chrom/moly 20" Medium incredably accurate BBL. 1 in 9 twist I shoot Sierra 65gr Game Kings out at nearly 3,000 FPS. Plus it balance's so well I mean point and shoot! Plus off a bench its "Bad to the Bone" It loves Sierra 53 gr Match in fact It loves all Sierra bullets.
longer is better in every which way
[QUOTE=ricky_arthur;388902]I have one in .223 with a 20" SS bull BBl and one in .204 with a 23" fluted BBl and both are heavy. There is no accuracy benefit to the 24 inch BBl but there are some down range benefits.
first of all you can't take to different calibers and barrels lengths with probably different twist rates and say there is no difference because yes long will make a difference in your range and your accuracy with 4 inches of barrel you can do what you do now with about 100 yrds added on check the stats.
I shoot an Olympis Arms K8 Target Match with a 20" stainless bull barrel. It shoots great and is well balanced.
For answers on AR's go to http://www.oa2.org/
There are some great guys there,they don't care which brand you shoot, even a few custom AR builders. "Rattler" works for Oly, "Dtech" is a custom builder, "Globemaster" and "John A." are very knowledgable, as are many others. I post as "Rob" on that board.
Wish someone would do this and create pages like this for every common caliber.
The Quickload and Quicktarget computer programs do a good job of predicting velocity (both muzzle and downrange) versus barrel length and powder charge. They don't tell much about inherent accuracy, but do directly predict wind deflection sensitivity, and help to predict relative sensitivity to vertical stringing vs velocity variations. It's not perfect but better than any other tool I know of. The programs give information which is not usually available from shooting tests which affect accuracy such as muzzle pressure, time to muzzle exit, and recoil distance at muzzle exit.
Originally Posted by DaRealViper
The factors which control accuracy is just too complex to make a meaningful prediction with a computer program or from shooting tests using a different rifle. You'd need plots of all powder types, powder charges, primer types, bullet models, barrel lengths, barrel contours, action type and stock models (plus other factors). In the test made by accuracyreloading it's apparent that the accuracy information is only useful for that specific rifle (and perhaps for another identical rifle). The velocity information is interesting and usefull, but it took a lot of effort to obtain the information and it's still only good for the limited selection of powders and bullet weights which were tested.
It would certainly be prohibitively expensive to do similar tests on all available chamberings and rifle models, even just the major commerical ones.
Last edited by Louis Boyd; 02-29-2008 at 07:48 AM.
For holding steady, and flat out performance from a static position, the 24" heavies are great. I've used them for coyote hunting and here in the midwest it didn't pose too much of a problem as walks to the calling locations were less than 1/4 mile generally. That said, I built a 17 Remington upper with 18" medium barrel (.900 under the hanguard and .750 gas block) for a general coyote rifle as it is much easier to tote around and quicker on the shot when they come in close and fast. I sold my last 24" upper to a friend that wanted it badly for prairie dog hunting but have the parts sitting in the shop to put together another one as for general target practice and varmint shooting they are ideal.
I'd suggest picking up that 24" heavy gun, and look at an 18 or 20 inch medium upper to add to the arsenal for the coyote hunting if you generally call them in.
I did make one shot on a coyote where that heavy barrel did come in handy once. It was just over 350 yards and I was snuggled into a snowbank on my backside. Coyote stopped for one last look and dropped at the shot (6" over the back hold or so). If you walk quite a bit on your coyote hunting excursions I would thing the shorter, lighter upper would be the better choice though.
Last edited by msalm; 02-29-2008 at 10:47 AM.