So I today I went to the range and successfully pulled an idiot move.  I have a Sandman L that I often swap between .223 and 300 blk. I also have the .22 cal end cap for the sandman when using that caliber.
Anyways, the idiot move I made is forgetting to swap from the 22 cal end cap to 30 cal when I went to shoot my 300 blk. Rifle was a H&R Handi rifle. Luckily it's only a one shot deal.  I realized my mistake after the first shot (I did see the round hit down range).  I immediately removed the spent casing and inspected the front of the Sandman.  I expected to see a blooming onion of an end cap or worse, but to my surprise, it looked like nothing happened.  When I did remove the end cap, there was some lead on the inside of cap.  But other than that, cap looked new. See pics below. Left is 22 cal, right is 30 cal.
Bullet was a Missouri Bulley Co. 245gr coated RNFP .309 diameter.  I was scratching my head on this one.  Is this type of bullet soft enough to pass through a 22 cal hole?  Is Dead Air products that tough?   All in all, I'm glad my Sandman and end cap are both healthy.

I think the real question here is, was it any quieter shooting 300 with the .22 cap?

Sorry for leaving that important info out of the OP. I didnt notice any noticable difference in the sound level. The Handi and Sandman is super quiet to begin with.

There are better ways to resize cast bullets you know.

Joking aside your lucky it was a cast bullet and not a jacketed one or you might be buying yourself a new endcap.  Also alot of folks would advise against unjacketed projectiles through a sealed suppressor.

I agree. .300blk and a Sandman sound great in a non semi auto firearm.  I have the K which is obviously louder compared to an L but through my bolt gun in .300blk it actually sounds considerably quieter with subs compared to my AR pattern pistol with the port pop and action noise.  One of these days hoping to get access to an S or an L just to do a back to back comparison.  I'd love to know just how much quieter it could potentially be.

Yeah, I kinda figured it could've been much worse if it was a jacketed projectile.  Is the problem with unjacketed projectiles in a sealed can the possible lead build up?

Go buy a lottery ticket!

This is a pic of an AAC M4-2000 (5.56mm/.223 can) that was mistakenly installed on an Arsenal 5.56mm gun that had been converted to 300 BLK, at a writers event in the late 2,000's. The writer in question proceeded to fire an entire 30 round magazine of Remington 220 grain subs through a 5.56mm can with a ~Ø.281 bore. The mis-step was discovered when the can was "checked-in" and it was noticeably heavier than it should have been. The pic was taken by Ten Pound Monkey after the can was EDM'ed to show the "damage".



Look at all that copper!

SilentMike

Holy shit

That’s wild!

Take calipers and measure the inner diameter of the hole in 22 cal end cap. They are obviously overbored to allow some clearance for the bullet and take into account slight misalignment or tolerance stacking between the can, the mount, the shoulder of the barrel, and the barrel shoulder to the bore center.

I wonder how much interference there is between the actual measurement of the hole and your 0.309" diameter projectile.

Oh man, I now want to subscribe to SilentMike's suppressor failure facts.

I might start a new thread looking for anyone wanting to share horror stories, suppressor cut aways, or just general stories from people within the industry. I can't get enough of this type of stuff.

That's crazy.  Thanks for sharing the photo.

Glad to share. That photo, in my opinion, is a testament to how well put together the old M4-2000 cans are.

I've seen cans fail in most ways you can imagine. Luckily, (knock on wood) I've never been around a can that failed and injured shooter or bystander. Launching a whole rifle can or having one barf it's guts out is a very big shock, recoil-wise. Don't recall anything I'd consider a failure with a rimfire can, and only a few with centerfire pistol. Had an experimental piston in a 45 can with improper heat treat shatter in testing and throw the whole can downrange. Most failures were with centerfire rifle cans, and most were cases of " it almost fits, let's give it a try".

With that said, I can't count the number of times either I, or someone else, has left finger or palm prints on a hot can. Occupational hazard.

SilentMike