0,0077 group!!!!

[alinwa]

Yes, there is a very dominant donut with 30BR - 30PPC creation. It is at the bottom third of the neck and unless your loading up some 150+ grain bullets you will not cause a problem. The donut is less if you fire form up the neck (Bullet down a junk 30 barrel or Pistol Powder with wad - you chose) as compared to using an expander. With an expander its mostly seen when you turn the neck it will be hit at the bottom and hard to get past.

Expander requires good lube and it will create a shorter case then a fire form. i.e. Mandrel on mine will yield 1.510 OAL while fire form will be 1.525. I have a custom expander so it allows a smooth cut on the neck - after two firings I recut with no change in the neck turner to skim off more of the donut that has moved around with brass flow.

I found with time that I don't consider brass ready for match until 15 firings and actually prefer 25+ to prevent tight brass due to hardening during the match (donut is gone by then). This number of firings for each piece of brass makes it difficult to keep them in sync across 100 plus rounds for a pre-load. I've broken mine down in to batches of 20 or 50 - so I can reload for a full match weekend if necessary. During practice I'm careful to keep the brass in sync (number of firings) by batch. The older the more consistent in sizing.

Holey cow...... this just gets better and better

This is real stuff. Really GOOD stuff.

Thank you...



al

 

[mks]

... after two firings I recut with no change in the neck turner to skim off more of the donut that has moved around with brass flow.

I just recently noticed the same thing! After 5-6 times neck sizing only about 1/3 of the neck, the bolt was hard to close on a few of the cases. A skim cut took off a tiny bit of brass at the neck/shoulder junction, and all the brass chambered easily again. I know neck sizing seems old fashioned, but I figure so long as the case fits back in the chamber, FL sizing can only make things worse.

I think the unsized part of the neck helps to align the bullet, so when I FL size, it is with a body die that doesn't touch the neck.

I found with time that I don't consider brass ready for match until 15 firings and actually prefer 25+ to prevent tight brass due to hardening during the match (donut is gone by then).

I have done well in matches with fire-forming loads. Another nice thing about the 30. But these are score matches, not world record groups like yours. Wish I had time to practice more...

This number of firings for each piece of brass makes it difficult to keep them in sync across 100 plus rounds for a pre-load. I've broken mine down in to batches of 20 or 50 - so I can reload for a full match weekend if necessary. During practice I'm careful to keep the brass in sync (number of firings) by batch. The older the more consistent in sizing.

Do you weight sort your brass? Mine are sorted and fired in order of decreasing weight, so that I am shooting cases with larger internal volume as temperature increases during the day. It may not help much toward staying in tune, but it can't hurt.

Thanks,
Keith

 

[mstinnett]

I just recently noticed the same thing! After 5-6 times neck sizing only about 1/3 of the neck, the bolt was hard to close on a few of the cases. A skim cut took off a tiny bit of brass at the neck/shoulder junction, and all the brass chambered easily again. I know neck sizing seems old fashioned, but I figure so long as the case fits back in the chamber, FL sizing can only make things worse.

I think the unsized part of the neck helps to align the bullet, so when I FL size, it is with a body die that doesn't touch the neck.


I have done well in matches with fire-forming loads. Another nice thing about the 30. But these are score matches, not world record groups like yours. Wish I had time to practice more...


Do you weight sort your brass? Mine are sorted and fired in order of decreasing weight, so that I am shooting cases with larger internal volume as temperature increases during the day. It may not help much toward staying in tune, but it can't hurt.

Thanks,
Keith

I do not weigh and sort brass.

All brass is trimmed to length, powder weighed to .02 gr. variance (preload or vials) and check loaded rounds to at or less than .0002 centricity. In a real match if they our out of these spec I wont use them (practice later). I use a tuner so my load never changes.

I also Juenke my bullets to +/- 5 points of a baseline bullet.

 

[Apollo]

Thank you Mr. Stinnett for taking the time to answer questions. Also, congrats on such an accomplishment. Curious, do you move your tuner during the match/agg (not necessarily during the group - but between relays)? If so, is it just trial and error or do you have notes/etc? Thanks for your time. Again, congrats.

Stanley

 

[mstinnett]

Tuning

Thank you Mr. Stinnett for taking the time to answer questions. Also, congrats on such an accomplishment. Curious, do you move your tuner during the match/agg (not necessarily during the group - but between relays)? If so, is it just trial and error or do you have notes/etc? Thanks for your time. Again, congrats.

Stanley

Stanley, I tune using a chart created using Density Altitude - I believe this is a better method then just Temp or Humidity (these will work too). I will change tune during match as the day heats up (DA goes up). The tune chart may take several weeks to stabilize (trust) and many good Saturday Morning tune sessions. I may make adjustments before I start the group after checking the sighter - but this does not happen very often. This process is not perfect as there are many variables that are not mapped or understood. An explosion inside a closed structure is a very violent act that sets off all kinds of vibrations. I also know under many shooting conditions - tune are the least of our problems (this past weekend we could not even see a line on the target)!