Have two AR a 20" Bull Varmint and a M4 both with 1:9 Twist…will this stabalize a Hornady 75BTHP bullet ?
1:7 is better, but you can still shoot the 75gr. in the 1:9 with a slight accuracy loss;) .
Tim:cool:
1:7 is better, but you can still shoot the 75gr. in the 1:9 with a slight accuracy loss;) . So I guess the answer to your question is no.
Tim:cool:
My Colt 6724 1/9 24 inch shoots Black hills 75 and Honady 75 tap at under an inch at 100 yards. so 75 is no problem for a 1/9. it’s pet load is a 69 grain .
75gr Hornady T2 has a GSTAB factor of 1.0x from a 1/9 16" barrel, the increased velocity from the longer tube won’t put it near 1.1 even. If you are shooting in anything but warm weather, you will notice a loss in accuracy and maybe even total destabilization. Also, some 1/9’s are “fast” and some are “slow”, so if you have a 1/8.8 vs. a 1/9.2, you will obviously be better off.
All barrels are alittle different. You could have 2 different 1/9 barrels and each could shoot different.
The best thing to do is buy a couple of boxes and shoot at different ranges and find out what she will do.
Slight accuracy loss? Total destabilization?? How have we determined this???
My 1:9 S&W M&P-15 shoots 40gr varmint HP or 75gr overlength Hornady AMAX equally well. Mag length 75gr and 77gr are no problem. My 1:8 match AR shoots expert at 600 yards with “totally destabilized” 75 AMAX.
I have a Bushmaster Varminter which has a 24-inch 1:9 twist barrel that absolutely loves 75-grain bullets. I have effectively shot this rifle out to 926-yards (10-inch gong) and it holds sum-MOA groups as long as the nut behind the trigger is tight.
But this same rifle doesn’t like the 77-grain rounds though. My suggestion is to buy a box or two and try it. Your rifles might do better than conventional wisdom recommends. Good luck!!