Here is a pic of a cutoff piece of brass. The walls are .0365" thick. From base to interior flash hole surface is .202". Expansion will definitely stretch the case walls, but with a .0365" wall, it seems there is more than enough to make up for it. I'll find out during the pressure tests today
My first custom chamber: 300 Ultra X! (Creedmoor was taken)
- Thread starter Mram10us
- Start date
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I can build the heck out of a House ..but you have me puzzled with your endeavor on this Rum !! Lol
Rum Man
No issues on finish that I could see. I always polish my chambers after. I'll take some pics of the chamber with the borescope after shooting today. Also, get some pics of the inside of some fireformed pieces of brass to see the interior differences
I like fiddling
. That lathe has made more work for me. I've made comparators for my cartridges, headspace making tools, jigs, jags, etc. Crazy what is possibleSend over the info on your lathe sometime ! I like a little trouble too !! Ha haI like fiddling
Rum Man
bigngreen
Well-Known Member
Im baffled by what you have going!! I've done this but never had this straight section your talking about.
So the end of the 300wsm reamer is inside the chamber when finished by x amount. The x amount is all the same diameter. I know you understand this stuff, so I must not be clearly explaining it. The diagram on the first page shows two arrows from .5563. That shows the flat from base to the ~.7 mark.
I'll text it to ya. Best tool I've ever had. Pays for itself in a couple rifle builds.
bigngreen
Well-Known Member
So are you driving the reamer .740 past the end of the cutting flutes creating an actual straight section in the chamber?
Can't remember the exact amount on the reamer since I was going off of headspace measurements. I can check later
Update:
Did the pressure test today at 300yards. The starting charge of 86gr h1000 with 230otm showed high pressure. I shot these:
86.0 3011
86.3 3011
86.6 3004
86.9. 3015
Pretty tight bolt lift on the 86.9 so I stopped. Back to the drawing board.
Bad: definitely need to fireform with light loads and make sure the bullet is in the lands or the case had a bit of crush. Had one case head separation on a loose fitting round.
So far, the cartridge isn't worth it if I can only get 3011 with a hot shootable load. Too early to tell though.
Did the pressure test today at 300yards. The starting charge of 86gr h1000 with 230otm showed high pressure. I shot these:
86.0 3011
86.3 3011
86.6 3004
86.9. 3015
Pretty tight bolt lift on the 86.9 so I stopped. Back to the drawing board.
Bad: definitely need to fireform with light loads and make sure the bullet is in the lands or the case had a bit of crush. Had one case head separation on a loose fitting round.
So far, the cartridge isn't worth it if I can only get 3011 with a hot shootable load. Too early to tell though.
I'll try r33 next. Also, get you guys some pics of brass when I get back home
playing with wildcats is expensive but a lot of fun and more failures then successes. I know I changed my 30-338 rum imp reamer a couple times and about to make another change for all the new bullets and brass that is now available
keep us informed and have fun.
keep us informed and have fun.
