Originally Posted by Wild_Bill
Hi I have converted large to small primer pockets. To do this the primer pocket is reamed slightly deeper on all cases to a uniform depth. Then I machine inserts from Stainless Steel. They are pressed into the cases with Loctite Wick in. I use a .062" flash hole for uniform ignition. I did this to Rem 6.8 SPC cases to test the diference between the two the small primers were better however most cases with large primers require them. The 22-250 case is about the largest that benifites with small primers in some instances any larger the large primers available will be as good or better.
But using an old primer cup jammed in does not sound like the cases will be uniform I would guarrente they would shoot better before the old primers were tried that is if the correct tension is obtained with the old large primer anyway.
Thank-you so much for taking the time to answer my question, it will be very helpful in the long run.