varminter .223
Well-known member
Started by single feeding 90 tnts at 29 and 29.5 grains of cfe blk. 29 strung and 29.5 was sub 1 inch for 5 shot but I always have inadequate neck tension to hold the tnts so I gave up until I had a smaller bushing in hand. I believe .300 would be the normal bushing size and I wanted to go a thou or two smaller but .297 was all Midway had and a buddy was ordering so I had him get one.
After the bushing made it I loaded some of the same 29.5 grain loads and 1 of them just hammered the case head and flattened the 450 primer. The gun was short stroking as well. I swapped bolt carrier groups and I still had the same short stroking problem. GB is a non adjustable stoner and it is aligned properly.
Next step I ordered some 90 gold dots which seemed to have ample neck tension when run through a regular sizing die.
I had taken the scope off the gun so when I put one back on it I decided to use three leftover .297 bushing 90 TNT loads to get rezeroed. I shot three of them while adjusting the scope and noticed things were not tracking right. The third one jams the gun and after I open it I see it blew the primer out and it was caught jamming up the next round in the mag. I pick up my other two cases and the primer had blown out of them as well.
So one shot completely destroys a case head bending the rim portion down leaving the parts that line up with the extractor an ejector in their normal positions. Case head measure .009" wider as well as the case growing .004" extra width just below the extractor groove area.
I can't understand why some with the greater neck tension would have pressure and some don't.
Some of these I may have pulled the bullet on testing neck tension and resize twice.
I'd say I'm going to move to 2200 or h4198.
Has anyone experienced any odd problems like this with cfe blk? I've seen on other forums where 18" barrels did have short stroke issue however these case heads look scary.
Hornady brass and .005 to .006 should bump btw
After the bushing made it I loaded some of the same 29.5 grain loads and 1 of them just hammered the case head and flattened the 450 primer. The gun was short stroking as well. I swapped bolt carrier groups and I still had the same short stroking problem. GB is a non adjustable stoner and it is aligned properly.
Next step I ordered some 90 gold dots which seemed to have ample neck tension when run through a regular sizing die.
I had taken the scope off the gun so when I put one back on it I decided to use three leftover .297 bushing 90 TNT loads to get rezeroed. I shot three of them while adjusting the scope and noticed things were not tracking right. The third one jams the gun and after I open it I see it blew the primer out and it was caught jamming up the next round in the mag. I pick up my other two cases and the primer had blown out of them as well.
So one shot completely destroys a case head bending the rim portion down leaving the parts that line up with the extractor an ejector in their normal positions. Case head measure .009" wider as well as the case growing .004" extra width just below the extractor groove area.
I can't understand why some with the greater neck tension would have pressure and some don't.
Some of these I may have pulled the bullet on testing neck tension and resize twice.
I'd say I'm going to move to 2200 or h4198.
Has anyone experienced any odd problems like this with cfe blk? I've seen on other forums where 18" barrels did have short stroke issue however these case heads look scary.
Hornady brass and .005 to .006 should bump btw
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