I recently purchased a Savage LRPV in .223 with 7 twist barrel. I am having problems finding a powder that the gun likes. I have tried different powders, Varget, RL-15, TAC with no luck. Is there anyone shooting the 75 Amax with the 7 twist? If so (1) Do the 75's in said twist like fast or slow burning powders? (2) What is your load powder? (3) I need enough muzzle vel. to shoot 600 and 1000 in F Class. I know that the 7 twist is made for the 80 grain bullets but I have 600 75's that I would like to shoot. I like the ballistics on the 75 better than the 80. I have some 73 berger bthp that shoot like a house on fire. I have only shot the 75's at 100 yd, does the fast twist need more range to settle down? Thanks, Wade
Re: 7 Twist Barrel and 75 Amax
i shoot 75 grain A-Maxes in my Hart 1-7" barreled .223 AI over 25.0 gr H4895. this gets me to 1K at my altitude at about mach 1.3 if i remember my dope right. you will probably only want to put 24.5 gr in a straight .223 case, and at sea level on a cold day, that may not be enough.
the twist is fine for the 75s.
i shoot 75 grain A-Maxes in my Hart 1-7" barreled .223 AI over 25.0 gr H4895. this gets me to 1K at my altitude at about mach 1.3 if i remember my dope right. you will probably only want to put 24.5 gr in a straight .223 case, and at sea level on a cold day, that may not be enough.
the twist is fine for the 75s.
Re: 7 Twist Barrel and 75 Amax
First of all, the 1:7 twist is not made for the 80s. The 1:7 was selected to stabilize the long M856 tracer round. A 1:8 twist is fine for the 80grain bullets and in fact you might even say that 1:8 was created for the 80gr bullets.
I have had trouble keeping the 75gr A-Max solidly supersonic in the Houston area (sea level) in cold temps (30-40F.) I used to run them with 25.5gr Varget in a straight .223 case. In warm temps, they were fine, but when it got "cold," forget it. I even tried 26gr but I was getting too antsy about that load and just could not see the velocity gain.
The 75 A-Max is fine at 600, iffy at 1000 in low elevations.
First of all, the 1:7 twist is not made for the 80s. The 1:7 was selected to stabilize the long M856 tracer round. A 1:8 twist is fine for the 80grain bullets and in fact you might even say that 1:8 was created for the 80gr bullets.
I have had trouble keeping the 75gr A-Max solidly supersonic in the Houston area (sea level) in cold temps (30-40F.) I used to run them with 25.5gr Varget in a straight .223 case. In warm temps, they were fine, but when it got "cold," forget it. I even tried 26gr but I was getting too antsy about that load and just could not see the velocity gain.
The 75 A-Max is fine at 600, iffy at 1000 in low elevations.
Re: 7 Twist Barrel and 75 Amax
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sig685</div><div class="ubbcode-body">First of all, the 1:7 twist is not made for the 80s. The 1:7 was selected to stabilize the long M856 tracer round. A 1:8 twist is fine for the 80grain bullets and in fact you might even say that 1:8 was created for the 80gr bullets.
I have had trouble keeping the 75gr A-Max solidly supersonic in the Houston area (sea level) in cold temps (30-40F.) I used to run them with 25.5gr Varget in a straight .223 case. In warm temps, they were fine, but when it got "cold," forget it. I even tried 26gr but I was getting too antsy about that load and just could not see the velocity gain.
The 75 A-Max is fine at 600, iffy at 1000 in low elevations. </div></div>
What are you using for 1000 yd round in F class? Are you having to run the 75 to the lands? I loaded some test rounds to lands will be testing this afternoon. Thanks, Wade
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sig685</div><div class="ubbcode-body">First of all, the 1:7 twist is not made for the 80s. The 1:7 was selected to stabilize the long M856 tracer round. A 1:8 twist is fine for the 80grain bullets and in fact you might even say that 1:8 was created for the 80gr bullets.
I have had trouble keeping the 75gr A-Max solidly supersonic in the Houston area (sea level) in cold temps (30-40F.) I used to run them with 25.5gr Varget in a straight .223 case. In warm temps, they were fine, but when it got "cold," forget it. I even tried 26gr but I was getting too antsy about that load and just could not see the velocity gain.
The 75 A-Max is fine at 600, iffy at 1000 in low elevations. </div></div>
What are you using for 1000 yd round in F class? Are you having to run the 75 to the lands? I loaded some test rounds to lands will be testing this afternoon. Thanks, Wade
Re: 7 Twist Barrel and 75 Amax
I run 80gr JLKs to 1000 yards. They will not stabilize in 1:9, that I am aware of.
When I ran the A-Max, I loaded them just shy of the lands. I load the JLKs about 0.15 into the lands, but not the A-Max. I never considered the A-max to be a VLD-type bullet that can be seated into the lands. others may disagree, I played it safe.
In my experience, you either load just off the lands or into the lands, this business of just "kissing the lands" never worked for me; you're in or you're out.
I run 80gr JLKs to 1000 yards. They will not stabilize in 1:9, that I am aware of.
When I ran the A-Max, I loaded them just shy of the lands. I load the JLKs about 0.15 into the lands, but not the A-Max. I never considered the A-max to be a VLD-type bullet that can be seated into the lands. others may disagree, I played it safe.
In my experience, you either load just off the lands or into the lands, this business of just "kissing the lands" never worked for me; you're in or you're out.
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