223 and 22-250

[Preda8or]

I am getting ready to order my first ever custom barrels. I'm going to order a 20" heavy varmint contour 1 in 8 twist .223 and a 26" heavy varmint contour 1 in 8 twist 22-250 select match from Shilen for my savage short actions, and plan on using 75 or 80 berger vld's,unsure which yet) and some 55 NBT's because I have a bunch of them. These are going to be mainly for long range hunting rig and informal,For now)long range target shooting useing Winchester brass. The question is about throat length what would be the optimal OAL of the cartrige and What would be the optimal neck diameter for both.

 

[BigJim]

I haven't gotten into custom barrels, but in reloading for my production rifles I will often run into the problem of wanting to use a heavier head that needs to loaded to a longer OAL than my rifle will accept.

Suggestion - research the loads you want to use for the heads you want to use. It will tell your what your OAL should be for that type of head and weight. Then request that the throat be milled to 0.002 beyond the max OAL. That way your round will chamber correctly and give just enough that you are almost on the grove but not quite.

As an example the Lyman Book says that a 75gr jacketed A-Max 223 remington should be 2.390" OAL so you would want the chamber and throat set to 2.392" and a 80gr jacketed HPBT should be set to 2.550" OAL so you would want 2.552".

Now these demensions are WAY beyond what is normal for a 223,2.260" OAL max) you will not be able to use 55gr 40gr even 69gr heads because there will be too much slop in the throat.

Just an opion

Good Luck
Jim

 

[rstreich]

I am getting ready to order my first ever custom barrels. I'm going to order a 20" heavy varmint contour 1 in 8 twist .223 and a 26" heavy varmint contour 1 in 8 twist 22-250 select match from Shilen for my savage short actions, and plan on using 75 or 80 berger vld's,unsure which yet) and some 55 NBT's because I have a bunch of them. These are going to be mainly for long range hunting rig and informal,For now)long range target shooting useing Winchester brass. The question is about throat length what would be the optimal OAL of the cartrige and What would be the optimal neck diameter for both.

OAL isn't a measurement that's used much unless you're concerned about fitting in the magazine. So, the first question is: Are you going to load these rifle from the magazine or will they be used as single shots? If they're going to be single shots, then you're wide open with choices.

Someone here might have a chamber set up for the bullets you want to shoot and come in with some real numbers. Lacking that, one thing to do is to make a few dummy cartridges--just seat the bullets you want to shoot in a couple of cases so that the bottom outer edge of the bullet is just above the neck shoulder junction of the case. This is sort of the ideal starting point. If you're having reamers made, just send the dummy cartridges off to the reamer maker and he'll make your reamer to fit. If you're not getting reamers made, some gunsmiths have separate throating reamers,and the skill to use them). The gunsmith can measure your dummy cartridges and cut an appropriate throat length.

The rub, as you'll quickly see when you make the dummy rounds up is that you're going to have to compromise. If you have something like a Stony Point tool, you can get a rough idea of the differences between the 55 gr. Nosler and the 80 gr. Berger VLD with it. You'll have to decide between seating the VLDs really deep in the chamber or not being anywhere near the lands with the little Noslers. You could also split the difference, but I wouldn't recommend that. I'd suggest that since you're getting the barrels to shoot the VLDs, get the chamber set up accordingly. You'll still be able to find a sweet spot for the Noslers.