Subsonic .45-70 and a silencer

[Hunter]

Good afternoon fine folks.
I am working up a load with a 420gr RCBS bullet and 11gr of Unique for the new Marlin 1895 Trapper in .45-70. I am currently working on the review and am hoping to get a reliable subsonic load to run through a few cans.
With such a light charge of Unique I was told to use Cream of Wheat as a filler to fill the case just to where the base of the bullet will touch. My question is will the Cream of Wheat be problematic when used with a silencer? If so is there another filler I can use or can I skip the filler.
I also have plenty of 800X but no load data. None of my rifle powders will be subsonic at starting loads.

Thank you.

[1Hawkeye]

Never use a filler with unique and yes that cream of wheat would damage the baffels in the can like a bead blaster. 10 to 12 grs of unique should be fine. I use a Hoch 500 gr with 12 grs of unique and am getting 1098 fps from a 30" bbl but a Marlin won't feed 500gr bullets. I would try 10 grs and work up towards 12grs.

[MarkP]

I have used Red Dot in my 458 Win under the LEE 405 gr FN with no fillers with decent SD's. Also in my 38-55 with greatly reduces loads. I am not sure but I would think cream of wheat would cause issues. I would try it without cream of wheat to see about powder position sensitivity, try some powder forward, and powder reward and record velocities. Tap bullet first on wood table before chambering, tap rim before chambering. Try some with the SAAMI twirl when chambering. Rotate between thumb and index finger and chamber horizontally.

[JimB..]

No filler.

I’d compare powder forward to powder rearward just for grins. If the difference is significant repeat with magnum primers.

[Larry Gibson]

Use no filler with a suppressor [I also don't use a filler with Unique loads in a 45-70] as the suppressor at best will soon clog up from the filler material and at worst it will damage the suppressor.

[Frosty Boolit]

I know that availability is lacking but I just can't see a better application for trail boss than this right here. Worth the money if you can find it.

[RickinTN]

Might try 9 or 10 grains of Red Dot also If you have any. I'm going to try 10 grains with my 330 grain bullet soon. I don't have a supressor.


Rick

[Daekar]

I know that availability is lacking but I just can't see a better application for trail boss than this right here. Worth the money if you can find it.

This is exactly what I was going to suggest. TB basically turns almost any case into a perfect vehicle for subs.

Alternatively, you could use a heavier bullet where the lowest safe charge is subsonic.

[Outpost75]

Better technical solution for heavy bullet, subsonic is to use the .45 Colt case and capacity load of 4198 or RL7, adjusting charge for 1050+/- 30 fps with 400-420 grain bullet. Common Green Mountain 1:16" twist gunsmith special barrel, use .454 bullet from Accurate mold cut to fit. Use .45 Colt chamber and custom throat to seat out to 2" overall ctg. length to achieve max powder capacity. About 22 grs 4198 or 24 grs RL7 in threaded 16" barrel.

[Hunter]

This is exactly what I was going to suggest. TB basically turns almost any case into a perfect vehicle for subs.

Alternatively, you could use a heavier bullet where the lowest safe charge is subsonic.

I cannot find Trail Boss anywhere. The bullet I am casting now is the heaviest available that will feed in the Marlin test gun.

[Daekar]

I cannot find Trail Boss anywhere. The bullet I am casting now is the heaviest available that will feed in the Marlin test gun.

Hmmm, well I'm not sure how much wiggle you have on OAL before you get feeding problems, but if you can't deep seat a heavier bullet, an alternative might be to just seat the existing one deeper to cut into the powder space and then cut your charge weight accordingly. When making 245gr subs for my 357mag, I have varied OAL by a large degree and you can tune for more or less powder pretty easily that way, especially if your gun isn't picky about the distance to the lands.

[elmacgyver0]

What cans?

[GregLaROCHE]

I don’t use fillers with smokeless powders. Giving the rounds a tap before shooting won’t hurt anything.

[Lksdmachine]

My comment doesn’t help for your platform much, but I’ll second the Trail Boss powder use for atleast your problem.

I’ve found a factory threaded NEF rifle and I have a blast with 515gr cast over 11.9gr of TB. It’s is impressive on steel and the giggle factor hearing the spatter fall through the tree canopy after impact.

Have fun!!

[jakharath]

I was thinking a heavier bullet with Trail Boss.

[PositiveCaster]

I don’t have a can but I still don’t use fillers. I measured the case fill of several powders in near subsonic loads using a seated 405-grain cast bullet in WW cases and WLRPs. All gave around 1200 fps in my 30” barrel.

12.0 Unique - 43% fill
16.0 BlueDot - 46% fill
23.5 IMR4227 - 51% fill

With these powders I found about 100 fps difference between loads with the muzzle tipped up versus tipped down prior to firing. Not enough difference for me as I don’t shoot squirrels with my .45-70s - but perhaps enough to pass the sound barrier for the OP under some circumstances.



.

[shootinfox2]

why not?

[Daekar]

why not?

I now feel obligated to start loading 45-70, and I don't even have a gun chambered in it.

[Markopolo]

You might wanna check this link out. Lots of data for 45-70 low vel loads with all sorts of different powders…

http://www.gmdr.com/lever/lowveldata.htm

hope this helps,

Marko

[Lksdmachine]

I now feel obligated to start loading 45-70, and I don't even have a gun chambered in it.

I had the same feeling last year. Didn’t know I was going to like the 45-70 so much when I started.
The painful lesson you are going to experience is the costs of brass. I cast and have scrounged brass at shows for a while and I’m sitting on several hundred rounds now. Once you’re over that spanking, it’s a lot of fun.