W44wcf, you were correct in your comments about my loaded length. I went to the Gunsmith's and we checked the loads in my chamber, They would not enter.
Then I measured the bullet diameter as loaded and found them to be about .318" to .319" diameter over the drive bands.
I took them home and ran the rounds through the sizer die, now the bullets were the same diameter as the case.
Went back to the Gunsmith's and we tried them in the chamber again, this time they would enter but not go flush with the Breech Face. I used a Dial Caliper to measure how much they extended and got from 0.080" to 0.088" "proud' of the breech face of the barrel and chamber, measuring 8 rounds.
Took the rounds home again and ran them through the Crimper die and they came out .298" bullet diameter.
Back at the Gunsmith's they now go into the chamber flush with the breech face.
Now I know they will shoot badly, being smaller than the .299" bore, but I think they will still function as test rounds for the Gunsmith's immediate needs.
I will need to load some more cases after trimming them shorter.
Calculations:
present case length =.912" to .914".
Loaded rounds with the "299153" bullet sit proud of the breech face by between .080" and .088".
Subtracting, It looks like I need to get the case length down to at least .832", but better yet, to about .826" as a maximum case length for this bullet in my chamber.
Also, after loading, I will need to run them through the sizing die to get the Drive bands down to the same diameter as the case.
An interesting exercise in practical 'try and fit' process.
Now thinking of possible variations in bullets, I believe I could trim my cases to between .800" and .810" inch, For My Chamber, and have no problems with the rounds going in flush with the Barrel Breech Face.
Of course these cases will be 'short' for the 90gr "31-090A" bullets but should still be 'shoot-able' with useful accuracy, so I will not trim all my remaining cases yet.
Some of the problem was of my own making, due to miss-measured bullets and leaving cases long as possible to allow more 'life' to them, figuring I could always trim them shorter if the mouth starts to split or gets damaged some other way.
Some of the problem was not having the chamber to try first loads in immediately to hand.
And some of the problem was my desire to fit my Chamber and minimize trimming of case length from as supplied.
But then again this is a 'learning experiment' anyway, so nothing is 'lost' in the process.
Best Regards,
Chev William