Anybody convert a M70 CRF LA BDL to….

Unless you are going smaller or larger in case diameter, I don't think you will have an issue.
That is why I asked the question….

6.5x55, 6.5 rpm, 6.5x284 all represent larger diameters and a change in length.

6.5 Sherman is the easy button, but I told myself I wanted a cartridge with factory ammo.

My goal is basically to launch a good hunting mono of 120-150 gr with a g7 bc over 0.25 to 3000-3200 fps with a 22" barrel. With easy to buy dies, brass and ammo. So…..seems like I have to give up something….hmm.
 
I converted a pre 64 into a 6.5 284 with no feeding issues. If you are doing a mod 70 crf just put 2 round in the mag and start to cycle the bolt you will know if the bolt is going to pick the up and feed.
 
6.5x55 slightly larger head size should feed with little issue.
6.5 284 same head size, larger body, shorter length, probably need some adjustment
6.5 RPM same head size, larger body, length designed to work in 30/06 length actions may need the same feed lip adjustments as the 6.5 284 but would give you lots of case capacity to play with. Brass may be an issue.
 
That is why I asked the question….

6.5x55, 6.5 rpm, 6.5x284 all represent larger diameters and a change in length.

6.5 Sherman is the easy button, but I told myself I wanted a cartridge with factory ammo.

My goal is basically to launch a good hunting mono of 120-150 gr with a g7 bc over 0.25 to 3000-3200 fps with a 22" barrel. With easy to buy dies, brass and ammo. So…..seems like I have to give up something….hmm.
Sounds like you really want a 280 A1. 3050fps with a 150gn through a 22" barrel is usual.
 
Sounds like you really want a 280 A1. 3050fps with a 150gn through a 22" barrel is usual.
I kind of agree with this.
I have loaded for a lot of .280AIs. With a 22", a 140 will pretty easily hit 3100+. A 150 will be above 3000. A 168 will be close to the 2900 mark. A 175 should get just a bit over 2800.

If you want to run a 120-150 in a 6.5mm with a standard BF, standard feed lips, and LA @ 3000-3200 in a 22", with available factory ammo, there are not a lot of options that will get you there that will feed reliably. 6.5-06AI would easily hit that 3000+ with a 140. But it is not factory. 6.5-280AI will get a touch more. 6.5 Sherman even more. The 6.5RPM won't get anything a 6.5-06 won't do. I have loaded for one and wasn't overwhelmed by the performance. 6.5-06 (not AI) performance. But it is a cool idea.

.270 Win is another option. Tons of factory ammo, but easy to handload for. 120-150gr bullets will be in that 3000-3200 range. Even 165, 170, 175 if you have the twist for those. You can go .270AI, and still shoot factory ammo if you want, then handload for more performance later.

6.5SAUM would easily get there, but Mag BF. Same with 6.5SS, 6.5Max, 6.5Mega, etc. You could do a bolt swap to a magnum BF. Even 6.5PRC would get close. 140s @ 2950 are doable in a 22". Might need to go with a DBM and CF mag though.
 
.270 Win is another option. Tons of factory ammo, but easy to handload for. 120-150gr bullets will be in that 3000-3200 range. Even 165, 170, 175 if you have the twist for those. You can go .270AI, and still shoot factory ammo if you want, then handload for more performance later.
I really like the 270 ai idea…how/where do I get good dies under $350? This probably seems like a dumb question, but I really don't know.
 
I kind of agree with this.
I have loaded for a lot of .280AIs. With a 22", a 140 will pretty easily hit 3100+. A 150 will be above 3000. A 168 will be close to the 2900 mark. A 175 should get just a bit over 2800.

If you want to run a 120-150 in a 6.5mm with a standard BF, standard feed lips, and LA @ 3000-3200 in a 22", with available factory ammo, there are not a lot of options that will get you there that will feed reliably. 6.5-06AI would easily hit that 3000+ with a 140. But it is not factory. 6.5-280AI will get a touch more. 6.5 Sherman even more. The 6.5RPM won't get anything a 6.5-06 won't do. I have loaded for one and wasn't overwhelmed by the performance. 6.5-06 (not AI) performance. But it is a cool idea.

.270 Win is another option. Tons of factory ammo, but easy to handload for. 120-150gr bullets will be in that 3000-3200 range. Even 165, 170, 175 if you have the twist for those. You can go .270AI, and still shoot factory ammo if you want, then handload for more performance later.

6.5SAUM would easily get there, but Mag BF. Same with 6.5SS, 6.5Max, 6.5Mega, etc. You could do a bolt swap to a magnum BF. Even 6.5PRC would get close. 140s @ 2950 are doable in a 22". Might need to go with a DBM and CF mag though.
I am surprised that the 6.5RPM will not do anything the 6.5-06 will not do. I guess the nearly 20gr more case capacity in the 6.5RPM is wasted?
 

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