Thread: Suppressor rear bush sizing

Originally Posted by Bushwalker

I don't run any rear bushes, 1 is DPT other is GBC/gun supplies, no issues with stuff falling between barrel and suppressor, accuracy is good.

ditto, DPT no rear bush here.

Originally Posted by vulcannz

ditto, DPT no rear bush here.

My concern with that approach is that if the suppressor was to come loose on the threads while shooting there is a real rish of bullet contact with the baffles, the end result of that doesn't bear thinking about. Pretty sure this is the reason the bush is there.

Originally Posted by zeropak

My concern with that approach is that if the suppressor was to come loose on the threads while shooting there is a real rish of bullet contact with the baffles, the end result of that doesn't bear thinking about. Pretty sure this is the reason the bush is there.

No different to a muzzle forward, heaps of people running them without issue.

The bush serves to protect the mounting thread if the can gets a bash

Originally Posted by Nick-D

No different to a muzzle forward, heaps of people running them without issue.

Good point

Me personally prefer a fairly big clearance. I check my silencers regularly to ensure they haven't come loose.

I found my rifles to group better with the rear bush(s) not touching. Then again - I prefer muzzle forward silencers.

Originally Posted by Fssprecision

Needs to be a good clearance, quite often the bore is not concentric to the outside of the barrel, you don't want the bush trying to tip the suppressor.

Even though I don't have any over barrel suppressors, but have owned a Savage with a terrible banana barrel.
The bore was straight and either end was concentric, but the middle was wildly off centre.
An armorer told me that this is not unusual even for premier rifles.
So out of curiosity, what do you do when the bush is only touching at one point on the barrel ?

Originally Posted by Hall

Even though I don't have any over barrel suppressors, but have owned a Savage with a terrible banana barrel.
The bore was straight and either end was concentric, but the middle was wildly off centre.
An armorer told me that this is not unusual even for premier rifles.
So out of curiosity, what do you do when the bush is only touching at one point on the barrel ?

Relieve it….open it up concentrically till it has clearance ie not touching all round…unskilled opinion….!

Another vote for not running a rear bushing. My DPT on the 7mm08 M7 been fine without it.

The bore is concentric at each end but is frequently eccentric between those points due to barrel straightening after profile turning. When I machine a muzzle I first check the bore for straightness and correct it if needed before turning and threading the muzzle between centres. I then clock the OD of the barrel at the rear bushing point and note any runout. I can then calculate the correct bushing size with a minimum size that will not exert any eccentric pressure. Bushing contact on an eccentric OD can cause accuracy problems, especially as the barrel heats up. A true concentric barrel will shoot better with the bush in contact.

Exactly what I was saying earlier but most on here know best ha ha