Teach me about hardness and lube for a suppressor

[Pmc]

I need some input from you experienced casters out there on boolit construction and correct lube for subsonic 308's in a suppressor. I have been reloading for a dozen years and hunting with suppressed subsonics for most of that time. Ranges are 100 yards and under. My 308 is 1 in 11.25 twisted. Generally I have been using 180 RN copper jacketed bullets right at 1050 fps. My main concern with casting is leading the suppressor or clogging it with lube. The suppressor body is steel with Iconel baffles and is not user serviceable.

Would you expect WW's to be soft enough to run subsonic without leading the bore?

What lube would you recommend?

Thanks for any help.

[Plate plinker]

Question. Why even mess with lead? If you can't service the can yourself you are screwed. Unless you want to fire many,many,many rounds I'd just stick with jackeded bool it's. That's my 2 cents.

[youngda9]

I didn't know there was a thing at a "not user serviceable" suppressor?

[Pmc]

Question. Why even mess with lead? If you can't service the can yourself you are screwed. Unless you want to fire many,many,many rounds I'd just stick with jackeded bool it's. That's my 2 cents.

To know if it was possible. Better to know than not right?

[Chicken Thief]

Well, lube can be cleaned out with boiling water.
I have seen 22LR cans with 10000+ shots and they are ugly on the inside but i see no reason why carb cleaner and ultrasonic cleaning wont remedy that.
Until then comfort yourself with the fact that an added crud layer on the inside will dampen your muffler even further than a clean one!

[Plate plinker]

Good point chicken. I know a guy with a j ciener 22lr way up there in rounds fired too without problems.

Good luck Pmc

[warf73]

Good point chicken. I know a guy with a j ciener 22lr way up there in rounds fired too without problems.

Good luck Pmc

But 90% of all 22 rimfire cans are user friendly aka can be taken apart and cleaned.

As for the .308 I agree with chickens post.

[Idaho Sharpshooter]

Now you know why I went with the YHM brand. It takes me about the same time to disassemble as to screw on or off the barrel.

If you can't take it apart to clean, you need to buy a Sonic Cleaner big enough to just drop it in for cleaning.

Rich

[JeffinNZ]

I simply would not buy a suppressor that can not be 'user serviced'. Both of mine strip down for cleaning.

[DrB]

Pmc, I haven't done 308 win load development yet... Mostly I've been shooting 7tcu with my 308 can.

I would go with a fairly soft and untacky lube that will separate well from your bulllet at your low velocity. My experience has been that at these velocities the demands on the lube weren't much. You could use a bp or low velocity pistol lube like tallow+beeswax, etc... You can find formulas in these pages.

Also, I would suggest that depending on your application ww is harder than you have to have. I have mostly been using 30:1 pb:sn alloy for my subsonics. You may need to exercise some care with your powder selection as I have found that the faster burners like bullseye and trailboss can still contribute to some leading/poor accuracy. A little slower burning pistol powder has usually worked better for me.

Also, what is your application? If you are hunting, I have been happy with a large meplat bullet with borerider nose like the 7mm hunter. A chamber castin is a great way to start so as to make an informed decision about mold nose/shank geometry for accuracy, no leading, etc. You probably should stick to around 180 gr or a bit more due to your twist, especially if that has been working for you so far. You can actually use a slightly heavier lead than jacketed bullet and have stability, everything else being equal.

if you are worried about lube fouling, fire a few full powered 308 loads through the can every now and then till the can is toasty hot. You will blast, melt, and entrain most of that lube out of the can pdq.

[Pmc]

Thanks for the insight DrB. This is mainly for deer hunting. I do switch off to full power load when the shots are longer.

[DrB]

Pmc, for hunting, I do like a large meplat bullet of relatively soft lead. My experience has been that I get good expansion at around 950 fps with a soft lead tin alloy and the large meplat ensures I am cutting a decent hole from the get go. Imho, a round or pointy nosed bullet of ww at these velocities for hunting is a bad idea unless you shoot it a lot, know your range vs. drop intimately, range your target if it is outside of about fifty yards, and
only take brainshots. A soft alloy and wide meplat is a much better idea.

While you are subsonic at 1050 fps at most temps you are likely to see, I believe most people push velocity too high for the best quiet work. Bullet flight noise is still relatively high as you are in the transonic flight regime where the air accelerating around the projectile exceeds the speed of sound and you get shock waves. Losing another 100 fps won't loose you much (you already have a rainbow trajectory out at 100 yds), and I think you will find it is noticeably quieter, especially with a half ounce or so of ideal brand wire pulling gel in the thread end of your can.

Re a "wet" can, while I didnt find that can on vs off resulted in any statistically significant "freebore boost" such that the can on resulted in higher muzzle velocities, I did find that a wet can decreased muzzle velocity slightly. I suspect this is due to "spray drag" occuring in the can. Using this combo to smack fox squirrels you can easily get headshots out to about forty yards, and the loudest sound to the shooter is bullet impact (a hit sounds like a bat hitting a bag of wet sand). Gun noise is minimal despite the proximity of the shot.

That summarizes most of what I've found so far. Good luck.

[Pmc]

I agree about transonic velocities and noise. Somewhere a while back I read some information from Paulson that said noise increased above .92 of the speed of sound. I use 1050 as a sample velocity but not an absolute. As you know there are many things that go into finding the right load.

I have found 170 gr 30/30 bullets to work well for killing, but have used 180 RN to up the weight slightly. My ideal would be a flat nosed 190 in a soft alloy for this gun.

I have a bottle of Ideal Gel I use some but came to the conclusion that for hunting it didn't offer enough benefit.

[Larry Gibson]

Many suppressors for high pressure cartridges are not user "serviceable. My Sionics is not also. Many do not have any idea how much carbon 41 - 44 gr of powder generates and how quickly it builds up in the suppressor. Carbon fouling is very hard and almost impossible to clean out. With in very few rounds the suppressor can no longer be taken apart.

I've had a Sionics for many years and have fired thousands of sonic full service rounds through it and sub sonic rounds. I have rebuilt it 2 times. In the past I have tried about every way possible to keep it clean for "user service" but gave up. However, it can be kept serviceable much longer if it is boiled out in a carb cleaner as suggested.

With sub sonic cast one must be selective about the lube as DrB suggest. I've used Javeliana and LLA on cast for numerous years with complete success using only enough lube to keep from leading not just filling up all the lube grooves. I use the following bullets in my .308W suppressed rifle; TL314-90-SWC, RCBS 30-150-FN, 311466, 411041, and 311299.

Larry Gibson

[David2011]

Charcoal lighter fluid is, IMO, a great solvent for boolit lube and mineral spirits also works well. Don't see why you couldn't immerse the can in lighter fluid or mineral spirits to dissolve boolit lube.

David

[DrB]

Yes, pmc, I did see what might be minima for group size at different spots in load development, but they were different for different powders and I think corresponded to increasing initial pressure too high for the alloy lube combo with the faster powders. Point is, if your goal is a particular velocity I think you may be able to find the right load.

Not to harp on it, but I found the gel with a slower bullet (~950fps) to be pretty significant in reducing gas noise. In your application if you are only taking a single shot on a deer and don't care about disturbing other animals nearby, then I can understand why using a wet can would be more trouble than it is worth. If you want to leave nearby animals undisturbed, then I would recommend it with the lower velocity. My aim was for nearby animals to at most glance over curiously and then go back to what they were doing.

Sounds like you are on the right track... If you are looking for specific bullets or molds, then if I were you I would make an inquiry with swede nelson as to what he currently has in stock that fits the bill, or maybe make a request for samples to forum members so you can try out several before buying a mold. Folks around here are pretty generous and helpful.

[Larry Gibson]

PMC

I use a very soft alloy with GC'd bullets for my sub sonic .30 cal bullets (311041 HP & 311299HP). I cast them of 30-1 lead tin alloy and with a muzzle velocity up to 1050 fps (transonic "crack" comes from the speed of the air moving around the bullet, not the speed of the bullet) expansion out to 50 yards is fairly decent. Even without expansion they "thump" game a lot harder than a RN as any bullet with a flat meplat does.

Larry Gibson

[JeffinNZ]

My take on the non user serviceable thing is the manufacturer does not want you to know what is inside.

[rosst]

i use WW for sub .308 & 7.62x39 with satisfactory results, Lyman 311284, 311291, 31141 with beeswax/lithium lube at 950fps
tried hollowpointing the bullets with a forster attachment and gained some expansion but little in the way of better performance over the plain as cast 170 grain 31141.
never had an issue with lube build up to worry about, you may like to try the LEE tumble lube, i used it for a short while untill i got a lubesizer
could be a problem shooting both lead and copper jacketed bulllets without carefull cleaning . ..
still use the .30 cals suppressed but moving over to the .45's . .. . HUGE difference

cheers

[yondering]

Seems like one of those "Ness safety bullet" molds would work pretty well for this application. PMC, if you haven't seen those, they are basically a wadcutter with a large hollow point. Should be very effective on game at subsonic velocity.

In my experience, carb cleaner and ultrasonic cleaners are useless for cleaning out a fouled suppressor; and the only solvents that will remove the lead and carbon from the can will also dissolve aluminum. Since your can is steel, that should be OK. I believe one of the solutions that works is a mix of hydrogen peroxide and white vinegar. Could be wrong about the vinegar, but I know it contained hydrogen peroxide. I read that on silencertalk.com a few years ago. Just don't use it on an aluminum .22 can.