bore too big?

[vaeevictiss]

So I'm working on my next form one can since my 308 one came out well. This time I'm making a shorty style 223 can. Reading the general concensus here, I decided to use SS freezeplugs.

Well I think I goofed. The first plug I tried to shape (using an old steel mouse ball) was off center, so I realized I needed to make a hole. I put them in the lathe and hit them all with a center drill... And this is where I should have stopped.

Well not thinking I kept drilling out to .265.

Well as you are expecting, once I put them back on the press, it stretched the holes to an average of about .340.
Now I know the bore on a .308 can is bigger than this, and people use 308 cans on 223 with nearly no audible difference, but being a shorty style, I'm feeling there is a lot less room for imperfection.

is this a big deal?

[RPM509]

The tighter the bore, the less gas, the less gas the less noise.
With a shorty you are already sacrificing some sound reduction, I would imagine
that the larger bore would also cause the can to be louder, by how much
I have no clue. Don't even know if it would be noticeable to the ear in difference.

If I was doing it, even on a shorty, I would scrap those and make newer ones
with tighter tolerances.

[curtistactical]

It depends a lot on baffle design, I run a .265 bore on 22cal. and a .344 on 30cal. My 30cal. can is only one decibel louder on my 10.5" m4 than my 5.56 can is. It pretty much comes down to how much turbulence you are creating with your baffles as to how much the bore size matters. Being a short freeze plug baffle design I would make sure the bore is on the smaller side as it could have pretty dramatic effect on decibel level.

[Historian]

It depends a lot on baffle design, I run a .265 bore on 22cal. and a .344 on 30cal. My 30cal. can is only one decibel louder on my 10.5" m4 than my 5.56 can is. It pretty much comes down to how much turbulence you are creating with your baffles as to how much the bore size matters. Being a short freeze plug baffle design I would make sure the bore is on the smaller side as it could have pretty dramatic effect on decibel level.

An interesting design fillip can be seen in the walls of the innovative and outstanding
Vitamix Professional Series 750 Blender*. They are half of a long slim
prism. The complex self-interacting pulsating turbulence generated on the vortices
create interesting and suggestive destructive interference patterns, reminiscent of fluid
logic controls.

The 'wind tunnel' like patterns are especially revealed when blending
a mixture of bananas, strawberries, chocolate, and protein mix for density.
[ Kahlua not necessary but most satisfying ... just add extra 10 minutes
of Kata work out to compensate.]


One could envision exploring such tapered indentation's possible use
as a starting place for advancing suppression design. Reverse of golf ball
dimples.

Just a thought.


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[vaeevictiss]

OK thanks for the tips. I'll probably scrap these even though it may or may not make a difference. Would just hate to find out after its all welded up.