Using silencer with barrel shorter than rating?

[Andielouroo]

I have a 30 cal can that is rated down to a 20” 300wm but have a 18” 300 wm I need to suppress. I have a 338 can in jail, but wonder how much harm I’d do using the 30 cal can on a barrel 2” shorter than it is rated for until I get the 338 can.

Any thoughts? I know the warranty will be void if I do.

 

[JMGlasgow]

Ratings are there for a reason.

 

[elwarpo]

While the velocity is lower at 18" there will be more pressure. Try calling the silencer manufacturer.

 

[86alaskan]

When faced with the same question, I just called the manufacturer. I was using a silencerco omega on a 16" 3006 pistol. They offered great advice and in the end said it was ok to use, since pressure would be very similar to a 308 at that length, which is ok.

 

[Fred @ Bison Tactical]

I think it might also depend on if your using factory ammo or handloads. I suspect all bets are off at shorter with handloads.
I agree it would be really worth a call to the manufacturer so they can ask the correct questions and give you a specific answer.

I have had discussions like this with TBAC, and they are a great source for advice on their cans in scenarios like this.

 

[tomcatfan]

The issue with shorter barrels is that the pressure that the suppressor see's increases. You shorter you go, I would expect to see a suppressor just turn into a pipe bomb eventually.