22 ppc - case length v trim length

[Clay]

Case length is 1.515. Trim length is 1.505. I have factory loaded Sako cartridges @ 1.515 - can’t close bolt on them. Norma fits - measures at 1.505. What to do? Take bullets out of Sako, trim case and reload? Rifle is a Sako- odd they do not fit. Don’t want to force anything for all the usual reasons.

 

[4g64loser]

Case length is 1.515. Trim length is 1.505. I have factory loaded Sako cartridges @ 1.515 - can’t close bolt on them. Norma fits - measures at 1.505. What to do? Take bullets out of Sako, trim case and reload? Rifle is a Sako- odd they do not fit. Don’t want to force anything for all the usual reasons.

I wouldn't guarantee that it is the case mouth hitting the chamber. Keep in mind that there have been a LOT of variances in "ppc" case and chamber dimensions. When I see any ppc chamber, it is a candidate for chamber casting unless I have VERY good knowledge of who chambered it and with what reamer.

To see if it is the case length without casting, coat the bullet and neck/shoulder area in Dykem. Or use a sharpie if you don't have dykem. Attempt to chamber the round. Extract and eject the round. Examine where the Dykem came off. There is a good possibility that the heads headspace dimension is different or that the projectile is seated out too far.

 

[Clay]

Excellent info- thank you. And yes, the 22 ppc being a wildcat round does have a lot of variation as you call out.

 

[4g64loser]

Excellent info- thank you. And yes, the 22 ppc being a wildcat round does have a lot of variation as you call out.

I've messed with wildcats, and a few non-SAMMI compliant reamers in "normal" chamberings and it's always a bit if fidgeting to get it "right". Part of the challenge.

 

[KRC]

I wouldn't be surprised if the issue is that you have a very tight chamber, rather than a length or purely headspace issue. The magic marker test should tell you. You might try to measure the diameter of the Sako vs. Norma rounds at several places. (Check and compare neck diameters as well, just in case.) The good news is that if this is indeed the issue, you may be able to resize the live rounds with a small base die (with NO neck bushing installed) or with a 6PPC small base die.