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smltownr
04-05-2016, 11:07 PM
I have finally aquired the components needed to load for my Type 99. Am using the Lee CTL312-160-2R which are dropping out of the mold @ .315 using Lyman #2. Barrel slugged @ 3.145. According to my Lee Precision Data Max OAL is 3.13 and Min OAL is 3.03. Seating to the crimp groove gives me a OAL of 2.9535. Not loading a 'hot' load. 65-70% of the difference between start load and max load. Tried to judge the distance to riflings by loosely seating bullet and chambering. Did not seat more, i.e. did not touch riflings unseated. My question is: is this within perimeters, or should I seat the bullet further out. At present this is seating the bullet .308 into the case. THX in advance. Smltownr

jonk
04-06-2016, 12:14 AM
Depends what you want to do. If you want to use the magazine, then seat to the max length to feed through it.

If you want best accuracy, seat just off or just touching the lands. If you're willing to shoot one at a time. IF that boolit will reach the lands.

Don't size to .308. Just seat as is, it's already at a minimum for over groove size.

Published OAL is just to fit magazine size, you can go longer without issue.

runfiverun
04-06-2016, 01:04 AM
I'd leave it at the present depth or maybe go a little more.
you need the neck tension to hold everything in place.
you're probably not gonna get to the rifling with that boolit so allow it to make the jump.
you need diameter for the type of rifling the 7.7 has [it's similar to the marlin micro-groove rifling which is a direct descendant of the lee-metford rifling]
315 sounds like all your gonna get so make the most of it.

smltownr
04-06-2016, 04:38 PM
Jonk, I did not mean to say I'm resizing to .308. By seating to the crimp groove, .308" is inside the case. I.E. seating depth. At this COL it fits the mag and cycles perfect. Runfiverun; With the style of rifling it was a bit different to measure, after slugging. It came out @ .3145. So .315 would be good there, I was just a little concerned about being .0765 short on the min. OAL. I could seat a little shallower but that would mean only .2315 seating depth. I kind of remember hearing this depth should be equal to one caliber at least, don't know where I heard that though.

runfiverun
04-06-2016, 04:44 PM
it's an old rule of thumb for jacketed ammo.
it helps get the powder burning better.

many of the older mil-surp rifles have throats that are big like this you kinda get what you get.
a larger nose diameter helps and a little run-up is no big deal as long as you keep the velocity's in a reasonable window.
I have a 31 cal mold here I had cut by Tom at accurate molds for my big throated 31 cal rifles it weighs about 235grs and is in a tapered loverign design to try and fill those throats better.
it still don't touch steel in some of them, and it don't shoot any better or faster than my 314299 [but man it has some oomph when it gets there]

smltownr
04-07-2016, 01:04 AM
Thanks for your input. I will try this set up first. I have owned the rifle for a year and still have not shot, sighted it in, etc. Will see how it does.