Powder to reduce first round pop with 44 mag

[someguy2800]

Hey guys,

I have a cheap monocore solvent trap suppressor that I form 1’d and move between a few different rifles. I have mainly been shooting it on a 9mm AR, and a 300 blackout AR with the gas port plugged. I load both with 700x and get practically no first round pop from either of them, but recently I threaded a 44 magnum single shot, and I get a very loud first round pop on the 44 mag shooting 300 grain cast with 700x.

I am thinking of getting another tax stamp to build another suppressor with more volume and smaller blast chamber just for the 44, but before I do that I’ll think I’ll play with some different powder to see if a different powder type reduces it. Any suggestions? I would think a faster burning powder would be better. 700x and tightgroup are the fastest powders I have on hand. I also have a few medium pistol powders like power pistol and CFE Pistol. Can’t get much of anything for powder with driving about 3 hours.

 

[Demi-human]

Anything that can remove the oxygen from the can before the first shot will work. CO2 gas from canned air sprayed in just before shooting or even the bore taped over.

Have you tried an ablative inside the can?
Water, grease, line pulling lube, hand sanitizer, light oil, even cooking spray.
The ablative materials don’t remove the oxygen in the can but I find they still work the same for my suppressors, keeping the first shot pop down as well as the entire session quieter.

I don’t think a change in powder will reduce the First Round Pop, but a lower bore pressure upon bullet exit is a good thing.

 

[someguy2800]

I have tried some water. I might just need to back off the charge weight a bit. It would be really nice to get it to work dry like it does in 9mm and 300.

 

[Gtscotty]

It's probably can related, but on the subject, CFE Pistol works well for subs out of my 16" 77/44. I use 7.6gr of CFE Pistol with cast 305gr HPs, and 7.8gr with 300gr Truncated. 7.8gr of longshot gives similar velocities (just over 1,000 fps).

 

[someguy2800]

I have just a little bit of that left. I think I’ll try CFE and tightgroup tomorrow and if it doesn’t make any difference I’ll probably build a new can.

 

[someguy2800]

It's probably can related, but on the subject, CFE Pistol works well for subs out of my 16" 77/44. I use 7.6gr of CFE Pistol with cast 305gr HPs, and 7.8gr with 300gr Truncated. 7.8gr of longshot gives similar velocities (just over 1,000 fps).

just a thought, are you using coated or conventional lubed bullets? I am using groove lubed bullets in the 44, powder coated in the 300, and jacketed in 9mm. I wonder if maybe the wax lube is basically flashing in the can?

 

[N555]

Something fast, like universal, HP38, win231, unique.
Those are the fastest powders I have seen a wide range of published 44mag loads using.

 

[Gtscotty]

just a thought, are you using coated or conventional lubed bullets? I am using groove lubed bullets in the 44, powder coated in the 300, and jacketed in 9mm. I wonder if maybe the wax lube is basically flashing in the can?

The 305 gr are these cast, lubed HPs, sized to .432.
https://www.gtbullets.com/index.php?main_page=product_info&cPath=8&products_id=19

The 300gr truncated I used were powder coat.

CFE Pistol worked well for me, that's most of what I've used and it's hilariously quiet until that 305gr hits something.

 

[someguy2800]

Something fast, like universal, HP38, win231, unique.
Those are the fastest powders I have seen a wide range of published 44mag loads using.

If you look in some of the older manuals or lyman's manual you'll find loads for much faster powders than those, like bullseye, 700x, red dot, ect... I am currently using 700x which is quite a bit faster than all of those.

The 305 gr are these cast, lubed HPs, sized to .432.
https://www.gtbullets.com/index.php?main_page=product_info&cPath=8&products_id=19

The 300gr truncated I used were powder coat.

CFE Pistol worked well for me, that's most of what I've used and it's hilariously quiet until that 305gr hits something.

That 305 grain bullet from GT is the same one I am using, also sized to .432. I'll try that load you listed above

 

[N555]

You might try 44spl cases if they will cycle in your gun, low charge volumes are usually more consistent in the 44spl cases.

 

[greyling22]

You might try 44spl cases if they will cycle in your gun, low charge volumes are usually more consistent in the 44spl cases.

he said it was a single shot. much easier to get powder puff loads to work with

 

[jmorris]

In the load manuals you have what powder has the lightest starting charge weight?

Pick it, just understand, it’s going to be a fast powder and probably pretty crummy to get the most out of the case volume available. As far as “magnum” loads go.

 

[Gtscotty]

In the load manuals you have what powder has the lightest starting charge weight?

Pick it, just understand, it’s going to be a fast powder and probably pretty crummy to get the most out of the case volume available. As far as “magnum” loads go.

Pretty sure he's shooting subs like I am, in which case getting the most out of magnum level loads is not a concern, and powders on the faster end are what you want.

 

[someguy2800]

In the load manuals you have what powder has the lightest starting charge weight?

Pick it, just understand, it’s going to be a fast powder and probably pretty crummy to get the most out of the case volume available. As far as “magnum” loads go.

Short of using a high explosive I’m already using the fastest powder I can get my hands on

 

[jmorris]

Short of using a high explosive I’m already using the fastest powder I can get my hands on

I have always liked VV N310 for what you are doing but Titegroup would be #3, just behind N320.

 

[Demi-human]

Short of using a high explosive I’m already using the fastest powder I can get my hands on

Which leads to removal of the oxygen from the can for the first shot. The best, albeit least practical, way to remove First Round Pop.

I just remembered @jmorris telling me about ports to the side of the bore in the baffles reducing FRP. I thought of doing this for mine while I was making them but they perform well enough for me. I am unsure if it would work with a mono core suppressor. Perhaps he could explain more about it.

 

[P Flados]

I have done a bunch of Quickload studies on what combinations reduce muzzle pressure.

Faster powders are good and reducing free air space is good. TG is typically one of the best.

Using 44 SP cases and seating as deep as you can will reduce free airspace. Then adjust charges to get sub velocities and you will be at your minimum muzzle pressure.

 

[someguy2800]

Its not a muzzle pressure problem because after I get the oxygen out of it on the first shot it’s very quiet. The first round pop however is obnoxiously loud. My chronograph has been broken for the last week but once I get that working or replace it I’ll do some more testing. I don’t have any 44 special brass but I can try shoving the bullet down in the case like a wadcutter

 

[someguy2800]

I finally got around to playing with this some more and I've pretty well solved the first round pop. I changed 2 things. I switched to jacketed bullets, and switched powder to titegroup.

I ordered a bunch of 300 grain XTP's to load. The first thing I wanted to try was seating them below the case mouth like a wad cutter. That does not work because the case is too thick starting about 1/2" below the case mouth and seating the bullet that deep bulges the case and prevents it from chambering. I started with loading the XTP's with my go to powder 700x, starting around 6 grains and working down. This still produced a nasty pop which started to go away at 4.5 grains, which is only 750 fps. I lowered the charge weight down one more step to 4.0 grains and got a squib about 10" down the barrel. Luckily it was easy to push out.

Switching to titegroup I started at 6 grains which gave 800 fps and no pop. Working up to 7.3 grains I got 1000 fps and not quite action movie quiet but much much quieter than before and barely any difference between 1st and 2nd round.

Next I decided to try my lubed cast 305 grain bullets again to see if they were also quieter with tightgroup. I was hoping I could get a nice 850 fps plinking load. The cast bullet loads were still very loud even working all the way down to 4.5 grains of titegroup. I believe what is happening is that the wax lube in the lube groove on the cast bullets is igniting inside the suppressor. Thats really the only explanation I can come up with. 7.3 grains with a 300 jacketed is way quieter than 4.5 grains with a 305 cast.

So I guess that settles that. I am probably going to try some powder coated cast at some point, but I will not be shooting anymore lubricated cast bullets with a suppressor. Its a shame because I have a lot of these 305 grain cast bullets with no other use for them. Maybe I will try to remove the lube and powdercoat them myself.

 

[P Flados]

Glad you made some progress. Your "problem" sounds really weird to me, but then again I have no first hand experience with cans.

Another thing you could try is to remove the traditional lube on a handful and try some tumble lube.

For a bulk "re-lube" job, a hot water bath followed by application of tumble lube would be easy.

 

[someguy2800]

Glad you made some progress. Your "problem" sounds really weird to me, but then again I have no first hand experience with cans.

Another thing you could try is to remove the traditional lube on a handful and try some tumble lube.

For a bulk "re-lube" job, a hot water bath followed by application of tumble lube would be easy.

First round pop is a condition where the first shot through a suppressor produces a loud pop sound because something is combusting with the oxygen in the suppressor. Consecutive shots are quieter because there is no oxygen left in the can. In my case when shooting the lubed cast bullets and 700x, the first round pop was loud enough to basically sound like a normal gun being shot which kind of defeats the purpose. I don’t have any on hand to try but I don’t think the tumble lube would help since it would also be combustible.

 

[adcoch1]

Boil a handful of your lubed bullets to get the wax gone and try shake and bake powder coating. It's easy and will probably solve the problem. I like cast 300 grn bullets in my 44's, so I'd probably shoot em up, but boiling will easily remove the lube.