30-221 Short Headspace?

[Fastshooter03]

Has anyone tried running a shorter headspace version of the 30-221 for use with subs only?
I was thinking the same OAL or maybe a shorter oal with the headspace further back the neck length would be increased and since those big bullets go so far into the case that might help?
There would be a limit to what you could do even with trimming the sizing die but it would be possible.
Just throwing the ???s out there to hear some pros-cons.

Nick

[320pf]

Has anyone tried running a shorter headspace version of the 30-221 for use with subs only?
I was thinking the same OAL or maybe a shorter oal with the headspace further back the neck length would be increased and since those big bullets go so far into the case that might help?
There would be a limit to what you could do even with trimming the sizing die but it would be possible.
Just throwing the ???s out there to hear some pros-cons.

Nick

Nick,

What are you trying to achieve or problem you are trying to solve by shortening the headspace?

320pf

[Fastshooter03]

I was thinking of taking away some case volume to maybe get away with a more consistent or lighter powder charge although I don't know what kind of load density is currently happening.
The faster burning powder charges like 7 grns of N330 with 220 mkgs? Or the really light charges of 4-5 grains for a subsonic 125?
The other thing was to compensate for the short 221 case oal I'm getting. I need to go to 1.350" to clean them up.
So that would be .050" less headspace if I wanted the longest neck possible with my reamer.
I know brass problems are no reason to make a different chamber but I plan on making a couple more 30-221s and it's not that hard to deepen a chamber.
I know throating might be needed as well with 220s.

Nick

[Fastshooter03]

OK, here's what I'll most likely do.
7.62 x 30mm. 1.200" case length. Trim a new set of dies down .200". Subsonic only. Make spacers for 10 and 20 rd mags due to the short OAL if used in and AR. Thinking I might do a bolt gun first.
If I can get 1050 fps with smaller charges and less fps deviations it will be a success as long as accuracy isn't affected somehow.

Nick