12.17x44 and 50/70 Govt.

[gregdownunder]

Evening gents.

I have a Swedish rolling block in 12.7x44 I am working up a load for.
A chamber cast actually gave closer specs to the 50/70 Govt than the Swedish round,so that's what I am shooting in it.(just have to turn the rims down a little)
Twist is 1/42,groove Dia .513, much the same as most original 50/70's.
In fact the main difference really with this particular rifle is the exceptionally big lands,mines .475, or 38 thou deep.
I am not sure how deep original 50/70 grooves were, but suspect it was somewhat less than this.
I am using a Lyman 515141 mold and sizing to .513, and wondered if I was going to run into any problems associated with such deep grooves.
I have tried shooting it with pure lead,which it shoots quite well with but thought I should try a 1/20 mix?

My loads so far have been :
65 grains Goex ffg by volume,dropped, slight compression.
No wad.
Federal 215  and WLR primers.
Pure lead 515141 sized .513,seated with just enough tension you cannot pull it out by hand, no crimp
Starline 50/70 brass with rims reduced to fit 12.7 rim recess.
OAL 2240, 10 thou off lands.

If anyone has played around with one of these Swedish guns or even the 50/70 in general I would be interested in hearing what worked for you.

Cheers,

GDU

[John Boy]

I am not sure how deep original 50/70 grooves were, but suspect it was somewhat less than this.

GDU, from my #1 RRB Musket, vintage 1884, the bore is 501 - 507 (pretty shallow, hugh?)
Couple of shootings with the rifle ...
First Range Test for the 50-70 Rolling Block ... has load data I used

Here's the load data I used at a 1000yd range with the rifle:
Lee 457-450F 457gr 0.22BC 1:20
Starline
CCI BR2
Swiss FFg 70gr
0.075 Felt Wad
1263 fps Avg  13.8 SD
5x Blow 6:00Hold on targets

At least I hit Homer, the buffalo, at 1000yds with a rifle that is only supposed to be 300yd gun.  Only had 3 lead splashes with the 7 ring being the best hit.  Homer is 82" wide and 48" high

This is the spinner that was next to Homer.  I consider this one of my BETTER misses.  My spotter said that when the circle on the spinner was hit, it was going about a 100 mph!

[bubba.50]

i too have a swede with chamber such as yours. when i got it and figured out(with a lot of help from dutchman) that it was supposed to be12.17x44 i ordered some overpriced bertram brass for it. loaded and shot it and all cases slightly bellied out. got some 50-70 brass and problem went away. i use .512 450gr. boolits with 60gr. goex and everything works fine. and with that overlength chamber i never have to trim brass. also, i don't resize. just compress a bit, use 2 milk carton wads and hand seat boolits. they squeeze down just fine in my gun. recovered slugs look like you could use a wrench on them. good luck and good shootin', bubba.

[StrawHat]

Evening gents.

I am using a Lyman 515141 mold and sizing to .513, and wondered if I was going to run into any problems associated with such deep grooves.
I have tried shooting it with pure lead,which it shoots quite well with but thought I should try a 1/20 mix?

My loads so far have been :
65 grains Goex ffg by volume,dropped, slight compression.
No wad.
Federal 215  and WLR primers.
Pure lead 515141 sized .513,seated with just enough tension you cannot pull it out by hand, no crimp
Starline 50/70 brass with rims reduced to fit 12.7 rim recess.
OAL 2240, 10 thou off lands.

If anyone has played around with one of these Swedish guns or even the 50/70 in general I would be interested in hearing what worked for you.

Cheers,

GDU

I use a trapdoor in 50-70.  For a lead recipe, 20/1 is fairly hard.  I have used it but now prefer the softer alloys like 30/1 and 40/1 in my big 50.  Other than that your load looks about like mine.  A grease cookie will help keep fouling soft and might be considered.  I use a good black powder lube between two card wads from a cereal box.  Some prefer wax wads from a milk box.