Over on AR15.com I offered to compile a bunch of data concerning how 7.62x39 preforms in diffrent bbl lengths. I figured I'd share it with you guy's first.

The rifles used for this test differed greatly from one another so please don't take this as "one size fits all" data.

The rifles used were as follows

1. A norinco 16.5" paratrooper SKS .310bore

2. is a 20" Model 1 Sales AR15 upper .310bore

3. a custom bolt gun with a 1/15 inch twist bbl that's 26" long and has a .308 bore

All chrony readings were taken at 12 feet with a model F1 without sky screens against a uniformly Grey overcast sky and an air temp of 55 degrees. Perfect chronographing weather.

Part 1 factory loads

154 grain WOLF sp


16' bbl........20" bbl........ 26" bbl
2042............2106............2273
2025............2110............2265
2015............2113............2261
2041............2125............2256
2033............2124............2250

avg velocity
2031............2115............2261



123 grn Monarch FMJ

16' bbl........20" bbl........ 26" bbl
2354............2432............2599
2345............2418............2595
2377............2405............2593
2315............2453............2548
2330............2422............2601

avg velocity
2344............2426............2587


125 grn Remington SP

16' bbl........20" bbl........ 26" bbl
2265............2261............2428
2238............2308............2444
2202............2304............2437
2191............2366............2485
2224............2264............2486

avg velocity
2224............2300............2456


Part 2 hand loads

for these loads the 26" rifle was omitted and the SKS had the gas piston removed due to slamfire and cycling concerns

170grn Sierra .308 diameter 30-30 flat point, magtech SR primer, 28.0grs H335

16' bbl........20" bbl

1921............1968
1924............1967
1931............1970
1936............1970
1896............1985

avg velocity
1921............1972

125 grn nosler b-tip, magtech SR primer, 25.5grs AA1680

16' bbl........20" bbl

2256............2359
2226............2355
2243............2361


avg velocity
2241............2358


The only real loser in all this is the anemic Remington ammo, this stuff just reinforces my assertion that anything METRIC factory loaded in this country is going to suck.

The most interesting find was just how fast and accurate these loads were when fired from as accurate platform as possible through a 26" tube

5 shot groups for the factory loads in the Stevens 200 were as follows
154grn Wolf 1.2"
123grn Monarch 1.37"
125grn Remington 1.0"
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Thanks for sharing. roger

Your AA 1680 25.5 grain loads and the Remington factory are a near exact match for my results over my Oehler 35P with the 16" Colt and like loads.

Thanks for the post.

Yes, these are different barrel lengths, but they are also different barrels. In order to make an accurate comparison, you would have to start with the 26" barrel and cut it sequentially to the shorter lengths. However, your tests are at least a representative sample of the same ammunition(s) fired from barrels of various lengths. It does give us a useful idea of what the relationships might be. Thanks for posting this info!

I very much appreciate the posting of all your info.

I have a pair of 7.62x39 uppers enroute here as we speak, and was curious as to what I might xpect from my DPMS and SGW uppers. Also very glad to get the 1680 data, as the brown truck just dropped off 1 M Hornady 123 gr. SP bulk bullets snd three magazines this afternoon, and I have a BUNCH of 1680 already on hand.

OORAH!! Looks like fun comin' on board.