Most specifically relating to a .243 Ackley and the fired case body versus the sized case. I actually like the apporximately .003 the neck has, but the body where the shoulder begins is apparently being sized nearly .008" This is I think a possible area of harm to my rifles accuracy.

Opinions please.

I think you're asking which would give better accuracy; full length sized vs neck sized cases. To find out if there is any impact on accuracy, you should try it both ways.

Neck sizing has real benefits with extended case life but in my experience doesn't always improve accuracy.

quote:

Originally posted by 308Sako:
I actually like the apporximately .003 the neck has, but the body where the shoulder begins is apparently being sized nearly .008" This is I think a possible area of harm to my rifles accuracy.

Opinions please.

I think in general it will be hard to say.

Whether a reduction of shoulder diameter (fired -> sized) of .008 will have a noticeable impact on accuracy needs to be verified by testing. As Grumulkin suggests, the easiest way to find out, is to use a neck sizing die, and see whether a tighter fitting case seems to produce better accuracy.

If your rifle actually likes a case more closely sized to your chamber, and you still want to FL size, a custom die might be the way to go. If you were shooting BR calibers (e.g. 6mm PPC) some of the die makers catering to that market (e.g. Neil Jones) might be a good place to start. Alternatively, I've had Hornady do custom dies for me with specified dimensions, and they have worked well for hunting type calibers and guns.

In general, I think it will be hard to predict for a given rifle, whether a particular dimension is of paramaount importance to accuracy. Testing will always be called for with the particular gun in question. The one exception may be the throat design, where it is likely that a size of no more than .002" over bullet diameter can probably be said to be advantageous to accuracy in general.

- mike

Hey 308Sako, I used to do some Wildcatting long, l-o-n-g ago and it finally wore me out. Just letting you know my information is dated.

If your Dies are RCBS, I know you can talk to them about sending some Fire Formed Cases to them along with the Dies and they will "adjust" the Die Dimensions to what they consider the proper size for that specific Chamber. Don't know if they charge for this now or not.

Anytime we deal with Regular Cartridges, we still have to deal with the extreme limits of the Dimensions. Wildcats seem to increase the odds that it just won't go perfectly if we don't have the Dies made with the firearm. It is just part of Wildcatting.

Best of luck to you.

Are you using Redding dies? If so , they make 2 different 243AI dies. They have 243 win imp dies for a .455 shoulder that resize to .452 and they have 243 Ackley Imp dies that are for the .460 shoulder and resize to .457 or so.


www.duanesguns.com

Yup, Redding bushing dies... got em through Sinclair.

Off to redding they will go.

Thanks all