Mosin Boolits

[DeadHandRed]

Hi all, im attempting my first cast boolits. have run in to a couple of issues.

When seating the boolits im getting some shaving. Also its hard to chamber a round, then on extracting the unfired round, the boolit gets pulled out.

heres my info

Bore:

Ive slugged both my mosins (91/30, M44) which come out at:

91/30: Lands @ .3016, Grooves @ .3118
M44: Lands @ .3024, Grooves @ .3142

Boolits:

Im using a 314299 mold which is dropping them .31495 around then bands. (and .3039 around the body)

I have a Lee setup and am using the .314 sizer, which is sizing the boolit (bands) to .3142. I have the .311 sizer but discounted using as its smaller (.3112) than both mosins grooves.

Case Neck:

My cases are full length sized (lee pacesetter set, swapped out the expander ball to .314 version)

Case neck measures .3032 (even though im unsing the 314 exp ball. didnt measure results when using the provided 308 exp ball)

i noticed little collet marks around the edge of the case mouth too.

So...

Shaving

after shaving the first boolit on seating i looked at how i installed the expander ball. the top of the expander ball was flush with the collet bolt as per instructions, so i set the expnder ball further down the die thinking maybe the closer the flare was to the case mouth the better the belling would be, didnt make any difference though so reset to flush.

pic of seated boolit

http://img441.imageshack.us/img441/4964/37071284.jpg

rubbed of the shaving for better look (excuse blurry photo)

http://img205.imageshack.us/img205/9931/88273849.jpg

So theres a little shaving, which im not happy about but im guessing that some would say its not the end of the world. i still think im not using the expander ball correctly.

Chambering

note: no primer or powder, just seated boolit.

After rubbing the shave off, i chambered the seated round (in the M44) and had to push quite hard on the bolt. Thinking about it now, I moved the bolt quite slowly and dont think the extractor grabbed the rim early on so i had to push harder than usual to jump it ver the rim probably, but thats not an uncommon thing for my mosin, and i remember what it feels like. wasnt really the same feeling. Then when i opened the bolt again i had to give it a bit extra and the boolit stuck in the barrel. easy to tap out.

i cant remember what the OAL was exactly but it was about 2 mm under the Max (77.14 mm) so about 75 mm

pic of the boolit after tapping it out

http://img861.imageshack.us/img861/6140/82443502.jpg

can see the scrape/rub where it was stuck on the front band, not really a dent/compression though.

im still reading about the throat of the rifle and learning whats going on (im a complete beginner about this stuff) and im guessing i need to shorten the OAL by some amount. but thought better to post results here and hopefully someone can point me in the right direction.

Cheers, red

[waksupi]

You need to flare the case necks to avoid shaving. From what you say, I believe the other problem is caused by seating the boolit at too long of an OAL. The projectile is jamming into the lands or throat, so can not be extracted easily. Seat them a bit deeper. This is also causing the hard chambering.
If they are still chambering hard after that, you may have thick neck on the brass, and have to reduce the boolit diameter a bit.

[runfiverun]

waksupi got it.
i use the next size up expander to just bump the case mouth against it gives the case mouth enough flair to accept the gas check portion of the boolit.

seat the boolit another half millimeter deeper.
some engagement of the boolit is desired, but not jammed in the throat.

you can open the 311 die to 312 yourself, by taking a dowell, cutting a slit in it about 2" long
wrapping wet dry sandpaper around the dowell and lightly oiling it.
then rolling the dowell back and forth on your leg or spinning it in a drill.
go slowly clean it up and measure often.

[DeadHandRed]

Thanks to you both


i use the next size up expander

whats the next size? is it a lee part?

Cheers,
Red

[buyobuyo]

+1 to what Waksupi and runfiverun said. Flare the neck and seat deeper. You can see what looks like rifling marks on the front driving band on the bullet you tapped out. Measure how long the marks are and set it back a little less than that measurement so you have a couple thousandths engagement with the rifling. The next size up from the .311 expander would be 8mm. Another option is Lee's Universal Expanding die (http://leeprecision.com/universal-case-expanding-die.html).

[mpmarty]

Quit messing around and get an "M" die. Problem solved. Also seat a bit deeper in the case to quit having an interference fit with the rifling.

[Larry Gibson]

+1 on the M-die and I suggest the .31 M-die. However, the Lee tool will do nicely if you don't size the necks so much. You can adjust the collet die out a bit to just size the necks down so the inside diameter is .002 - .003' smaller than the sized bullet diameter. You don't need to size the neck as much as you are.

Larry Gibson

[runfiverun]

the m-die will work, lee i think makes one too.
i never knew about the m-die,and just used what i had available.
the 8mm will work just fine you only want enough to get the g/c in the case.
remember to champher the case mouth too.
if you have the wherewithall you can make a tapered rod to open the neck mouth area to fit the press.

[wallenba]

Quit messing around and get an "M" die. Problem solved. Also seat a bit deeper in the case to quit having an interference fit with the rifling.

Another vote for the 'M'. They solved my problems without overflaring the brass. They get you seated more squarely too.
Also, are you chamfering the inside of the case mouth?

You can also try opening up the Lee sizing dies with 400, 600 and 1500 grit emery paper on a dowel driven by a cordless drill. Checking them periodically with lead slugs through the die. It's an easy way to get closer to ideal cast boolit diameters. Beagling the mold will help drop the boolits a bit bigger if needed. All that info is searchable here, if you don't already know how.

[Boolseye]

Hmm. Definitely too much shaving. Also...seems like the neck may be getting sized down too much. I don't know what the expander plug is in those Lee dies, but it strikes me that it may be a little small. I use a modified Lee .308 neck sizer die, with a washer around the case to activate the collet sooner ( so as to avoid bumping the shoulder on the Russian case), and an improvised mandrel that measures .310 for those bigger bullets. I happened to have a motorcycle bolt that was just the ticket.

My full-length set-up is an RCBS, which comes with a .310 expander plug as well as a .308. No shaving, ever. I also debur the cases inside and out before loading.

This post is meant to aid–if none of it applies, please ignore. Also, feel free to P.M. me if you would like further explanation on any of the points I made.

[DeadHandRed]

Thanks to you all, ill look in to the m-die i think. i had another go last night with no shaving most of the time so will have to look at what im doing different. i was making sure i put a bit more chamfer on the inside of the mouth. i was under the impression chamfering inside was a less is better deal (maybe that was jbullet theory).

seating depth is good now too. thanks again
Red

[Boolseye]

M-dies are great. Check out the Lyman multi-expander die, which has plugs for seven or eight calibers. It's all I use.
http://www.midwayusa.com/product/748976/lyman-multi-expander-and-powder-charge-die