M38 Mosin Nagant velocity data w/fat 311041

[Junior1942]

First a little info. If you remove the M38 front sight you can drive the sight pin out the bottom of the sight. Stick a punch through the hole in the top of the sight shroud and give it a couple of light taps, and the pin will come out the bottom of the sight.

NOTE: mark the bottom of the pin and the bottom of the sight so you can replace the pin exactly like it came out.

These data uses surplus 4895 and the group buy fat 311041 cast of air cooled ww alloy. Lube = LLA, two coats; gascheck = Hornady; size = .311" Lee push through die; weight RTL = 182 grs.

All Chrony readings are one shot only. Caliber 7.62x54R. Groove = .317". Bore = .304".

2.2cc = 1457 fps
2.5cc = 1673 fps
2.8cc = 1826 fps
3.1cc = 2156 fps

The barrel had zero lead.

An eariler sight-adjustment two-shot group with 2.2cc S4895 put 2 in 1/2" @ 60 yards. :)

[Baron von Trollwhack]

After I got my sight pin out, I drilled and tapped the hole to 6-32, turned off the top portion of thread in a screw, cut overlong, filed opposing flats and reassembled. Who knows where shootin' takes ya?

[Junior1942]

Baron, you're a genius.

[JeffinNZ]

Why are you sizing .311 for a .317 groove?

[Junior1942]

Because that's the biggest sizing die I have. And the bullets are .312". They seem to be obturating and shoot just dandy.

[JeffinNZ]

What a frightfully forgiving rifle. All power to you.

[Junior1942]

If it ever stops raining I'll see if those 2 in 1/2" @ 60 yards was a fluke.

[shooter575]

Hey Jr,by my looking at the weather channell you got a ways to go!I wonder if the Texans that were crying for rain a couple months age prayed a bit too much?
Hope all you fellas can stay dry!

[Junior1942]

The 2 in 1/2" @ 60 yards was a fluke. First, I re-checked and the groove dia = .312" and the bore = .302". Actually, I read the micrometer wrong the other day. That's the good news.

Bad news = the fat 311041 doesn't shoot well in it at all.

With 3.0cc S4895 for ~2000 fps, 3 shots @ 25 yards = ~18" with all three shots hitting the target sideways.

With 3.1cc S4895 for ~2156 fps, 2 shots @ 25 yards = ~4" with one bullet hitting sideways.

[texas tenring]

What year M38?

All that I've checked slug .314 for a groove diameter. Most WWII era 91/30's and 38's seem to be about that .314 dia. older Mosins will sometimes run less dia. and Finn barrels will usually run .310-.308. I bet if you find the right boolit and velocity it will shoot!

Good luck!:-D

[twotoescharlie]

Junior,

my m38 has a scout scope setup on it, it shoots 1 1/4 inch groups at 50 yards. Iam using the fat 30 as cast TL with 18 grains of 2400. this is the only load I have tried so far. I slugged the bore but don't remember what the size was. it is counter bored and from the looks of it has quite few rounds through it. the bore is a little dark but the rifleing is prominent. no problem with leading.


TTC

[Junior1942]

It was born in 1942, same as me.

Twotoes, your M38 sounds exactly like mine. I'm gonna dig a can of 2400 out of the freezer. Results tomorrow--maybe.

[twotoescharlie]

mine is a 1943 and and that makes it 6 years younger than myself. also it slugs out at .315-.316

TTC

[4060MAY]

Junior
have any WC820 (fast lot)?15grs with WLR primers
target below. born in '42 also so you know about eyesight.
not phenomenol groups but consistant.
not the same boolit but close, the fatter .30

[4060MAY]

picture of target

[carpetman]

TwotoesCharrlie--Yours is a 1943 and makes it 6 years younger than you. They have to be an exact match. It will never work with that 6 year difference. Something that obvious doesnt even require cerrosafe to determine. You need to find a 1943 from this board to match it up with. Did I tell you I'm 1943?

[Junior1942]

The WC820 and 2400 loads didn't work either.

WC820 (n) 1.0 cc = 3 in 5" @ 27 yards. One round hole, one oval hole, one sideways hole.

2400 1.3 cc = 3 in 12" @ 27 yards. One oval hole, two sideways holes.

I'm gonna order Lee .312" and .314" dies. Ideas????

[4060MAY]

I have Nujudge's 6cav GB, casts at .315-.316 .306-.307
the fatter .30 cast .316 .304-.305 with my alloy

[Junior1942]

My re-micrometer of the slug was with the wrong slug. . . . A carefull reading of the right slug gives me .3055"-.306" bore and .3175" - .318" groove.

It's back to square #1. A .311" bullet in a .318" bore ain't gonna cut the mustard.
No wonder it keyholes!

[Ricochet]

Might be good for paper patching.

[Junior1942]

I used as-cast fat 311041 bullets. I let the case necks seat the gaschecks. I put a daub of LLA on the bottoms of the bullets, for glue, then I pushed the bullets down on the gaschecks, then I rolled the bullets in LLA.

I used 3 fired cases with no sizing at all and 3 with neck sizing. The 3 with no sizing, I didn't even bell the necks as the gas checks started just barely. Load was 1.0cc WC820(n) for I guess 1500 fps. Range was 27 yards.

No sizing = 3 in 1/2"
Neck sized = 3 in 1 7/8"

All 6 holes were perfectly round. As a raw gascheck = .319" in dia, looks like they sealed my .318" bore enough for the .312" bullet to obturate.

Looks like the sized necks swaged the gaschecks and the bullets down a little and lessened the accuracy of those 3 rounds.

[gregg]

I used as-cast fat 311041 bullets. I let the case necks seat the gaschecks. I put a daub of LLA on the bottoms of the bullets, for glue, then I pushed the bullets down on the gaschecks, then I rolled the bullets in LLA.

I used 3 fired cases with no sizing at all and 3 with neck sizing. The 3 with no sizing, I didn't even bell the necks as the gas checks started just barely. Load was 1.0cc WC820(n) for I guess 1500 fps. Range was 27 yards.

No sizing = 3 in 1/2"
Neck sized = 3 in 1 7/8"

All 6 holes were perfectly round. As a raw gascheck = .319" in dia, looks like they sealed my .318" bore enough for the .312" bullet to obturate.

Looks like the sized necks swaged the gaschecks and the bullets down a little and lessened the accuracy of those 3 rounds.

Cool Junior. Nice thinking.
On the group buy board I posted a post asking if the Fatter 30 might ever come
back.
Junior an 8MM lee mold might get you in the right field. The cast bullet book I receved with my membership to the CBA told of good shooting with bullets .004
over the bore size. I have not tried it myself but know that the 30 cal. bullets keep working better as they increase in size for me. A work in progress.
Buckshot might be our hope for a sizer bored out to size.
GO Junior

[gregg]

Junior get over to the GB board. Intrest is building
on a nother Fatter 30.