.223 and 40gr projectiles. COAL differences.

[Parabuteo]

I would never read too much into OALs as it is such a moveable goalpost.

If you look a the SAAMI spec for the cart it will invariably be different to various manufacturers figures. In my case life is fairly simple as all of my rifles (1 No4 and 3 ARs) are all mag fed, so the best OAL is mag length and then mess with the load for the harmonics.

In some ways you can cheat the effects of variable seating depth (or at least seating into the landes) by crimping, and we would not want a bullet that is being thumped into a chamber via a splined barrel extension to have too long a seat anyway.

Different to hunting I know, but the point is that there are many variable to mess with, so dont worry too much. There is usually a way

[severnsider]

I would never read too much into OALs as it is such a moveable goalpost.

If you look a the SAAMI spec for the cart it will invariably be different to various manufacturers figures. In my case life is fairly simple as all of my rifles (1 No4 and 3 ARs) are all mag fed, so the best OAL is mag length and then mess with the load for the harmonics.

In some ways you can cheat the effects of variable seating depth (or at least seating into the landes) by crimping, and we would not want a bullet that is being thumped into a chamber via a splined barrel extension to have too long a seat anyway.

Different to hunting I know, but the point is that there are many variable to mess with, so dont worry too much. There is usually a way

Thanks for that. Yes, I'm going to carry on using the SAAMI length. I was just particularly surprised at the very short OAL suggested by Vihtavuori. I'm not going to try it!

[Parabuteo]

Thanks for that. Yes, I'm going to carry on using the SAAMI length. I was just particularly surprised at the very short OAL suggested by Vihtavuori. I'm not going to try it!

If I tooks right...It probably is right chap. The thing is that the charge weight alone can hugely change the harmonics. On my old Dolphin (remember the green piece of Mecano?) it was almost precisely 0.6gr between nodes. The group used to tighten up around those weights.

Russell Simmonds proved a point be seating the bullet deeply (about 50 thou deeper) and it shot the same. It often depends how twangy the barrel is to start with I guess

People often get tied in knots trying to wring the nth degree of group size out of a load, manage it once when the stars were aligned, and burn a barrel out trying to defy physics, when they may do better settling on a stable and predictable load and burn a barrel out practicing positional or wind reading.