77gr in a 8"twist

[Ironworker]

77gr TMK in a 8" AR-15 ?

 

[LiveFire]

Works fine. COAL can be difficult depending on powder. ASC ss mags let you load to 2.31 oal. It helps if using something like varget. If using ball like AA2520 or Tac 2.26 is easy.

 

[mace2364]

Yes, I’ve been doing just that for a long time. My “long range” .223 has a 1/8 barrel, and Ive shot 77s out to 1000 with it.

eta-I was using SMKs but I can’t imagine you’d have trouble with TMKs

 

[RegionRat]

Zoom in on the last line. 1:8 twist is fine for the 77 TMK.


And here is an SG estimate for sea level and 2650 fps.

The 77 SMK is one of the most popular XTC competition bullets. The TMK is younger, but gained popularity because it is mag length ammo with a BC that is closer to the 80 SMK than to the 77 SMK.

 

[sandwarrior]

Yes, I’ve been doing just that for a long time. My “long range” .223 has a 1/8 barrel, and Ive shot 77s out to 1000 with it.

eta-I was using SMKs but I can’t imagine you’d have trouble with TMKs

You won't have problems stabilizing the 77 SMK pr TMK in a 1-8" twist. You may have a problem shooting them from a magazine if seated too deep. I can't feed 75 A-max's from a magazine. Thus, why I shoot BTHP's.

 

[Big Mc]

77gr TMK in a 8" AR-15 ?

Works just fine in my JP with a 28 in barrel. Tommy Mc.

 

[riverside jeep]

I just picked up the Midway deal on their bullet seconds, 77 grn match boat tail hollow points that everyone believes are SMK. Shot my best group ever out of a 18' 1/8 AR-15. Measured at .297"

 

[cmysix]

and looking at the MFG's twist rate chart would be out of the question?

 

[RegionRat]

and looking at the MFG's twist rate chart would be out of the question?

Yes. It is shown on the picture of the Sierra splash up above in post #4.

 

[Fuj]

I have a Rock River Delta Mid with a 9 twist HB. I shoot IMI MOD 1
77gr Sierra's. It shoots them just fine. For some reason it don't shoot
the Mod1 69 grain worth a damn, in either the 9 twist or my Rock
River EOP 8 twist bull barrel. Both love the 77.