Lyman 7mm silhouette bullet in a Remington Rolling Block

[brstevns]

I have been trying the Lyman 7mm 160gr Silhouette bullet in my little rolling block carbine and everyshot key holed?

[runfiverun]

the 145 won't do any better.
you need diameter, I'd bet that throat will accept .290 without issue.
probably a 284ish nose wouldn't be a bad idea.

[44man]

Not enough drive length on the boolit for the gun would be my guess.

[brstevns]

How about the standard LEE 130GR BULLET MOLD

[brstevns]

Alright I traded the 7mm sil bullet mold for a 150gr Lyman Loverin design. Hope that works out better.

[Harter66]

Funny that I'll follow this if you'll post it up. I load for 3 7mm and all 3 tumbled the Loveren types from gallery to game loads. 1 of them will take a 300 dia back in a fired case so that probably doesn't help.

[Larry Gibson]

Have you slugged the bore? The throat?

Larry Gibson

[MtGun44]

Never even tried cast in my Rem RB 7x57 because I know the bore is very worn
and very oversized. I just shoot 175 RN Hornady for hunting in that one and leave
it alone otherwise.
HOWEVER - you may be able to get a .288 or so cast to work, depending on your
individual rifle's bore condition.

Bill

[brstevns]

My RB has a 287 bore so going to give the Loverin design a try. The 7mm Lyman SIL mold I had was making a 284 at the lands and around 279 at the nose . Will know more after the weekend. If the weather holds I plan on heading to the range.

[brstevns]

Bad day at the range. The 150gr Loverin bullet key holed. I am not giving up for one reason. The bullet was sized to .285 and my bore is .287 on the old rolling block. I opened up the Lee sizer die to .288 and will try some at that size. The load was 20gr of IMR 4227.

[MtGun44]

Should work if you can get the boolit to touch the bottom of the grooves, plus .001-.0015 on each side.

Bill

[brstevns]

Should work if you can get the boolit to touch the bottom of the grooves, plus .001-.0015 on each side.

Bill

Maybe I should size to .290? The next step I would think, would be to open up the seating die?

[brstevns]

Alright tried the 150 again, sized to .288, still key holes. The good thing is at least it was hitting the paper at 25 yards. Going to try sizing to .290. Keeping my fingers crossed.

[MtGun44]

Good luck, please report back. I have one and may try boolits if you have success.
I always assumed it was near futile and left it alone in that particular rifle - which is
very accurate with the Hornady 175 RN. My bore is very worn and very large, just
seemed unlikely to work at anything remotely like normal 7mm mold sizes, when you
look at a .308 groove diam rifle needing .310 to .311 in most cases for best accy.
Then take a .287 groove diam (not bore) and add that same .002 to .003, you get
.289 to .290, and then add in my worn rifling. . . . .

Bill

[brstevns]

Good luck, please report back. I have one and may try boolits if you have success.
I always assumed it was near futile and left it alone in that particular rifle - which is
very accurate with the Hornady 175 RN. My bore is very worn and very large, just
seemed unlikely to work at anything remotely like normal 7mm mold sizes, when you
look at a .308 groove diam rifle needing .310 to .311 in most cases for best accy.
Then take a .287 groove diam (not bore) and add that same .002 to .003, you get
.289 to .290, and then add in my worn rifling. . . . .

Bill

Sounds as if we have the same rfle. Have yet to try the J-words in mine. What type of acuracy are you getting?

[brstevns]

I went back to the range today and tried a bullet sized to .2885. Going slow with the sizing. Tried 10gr Unique this time. Only fired 4 rounds 1 full keyhole, 1 half keyhole and the other 2 were almost pefect round holes. This is with the bullet PC coated and a gc added. Range was 25 yards, plan to try .290-291 dia. next

[MtGun44]

1" or 1.5" for 5 at 100 with 35 ish (from memory) grains of 4064 under a Hornady
175 Rn. Mild, accurate, done fiddling. If you have other 7x57s do NOT use brass
shot in the RB in them, just neck size and go again. WAY oversized chamber, so
full length sizing is counterproductive to brass survival. Lee collet neck sizer is ideal.

Bill

[JeffinNZ]

There have been articles in the CBE journal about 7X57's with MASSIVE throats. You could paper patch your 7mm bullet.

[brstevns]

There have been articles in the CBE journal about 7X57's with MASSIVE throats. You could paper patch your 7mm bullet.

That will be my next step, if I cannot get .290-.291 bullets to work. So far pressure signs are fine.

[brstevns]

Update! Tried the Loverine bullet size at .2905. Not getting key holes anymore but not perfect round holes either. Going to try .292 next. Tried some PP .277 bullets wrapped and size to .2905 these all keyholed. Load was the 10.5 Unque load for both.