Using moderators of larger size than rifle calibre

tjm160

Well-Known Member
Clearly so long as the thread is compatible, can a .243 moderator be used on a .223 and if so, what are the drawbacks? I assume the hole larger than the round needs would just let out more gas and cause a bigger bang, than a moderator the correct size for the calibre? The reason for the question; I'm considering using my .223 slot and would rather save £300 on another moderator, if it is feasible to use my .243 moderator. Thanks in advance for any advice/guidance.

Tim
 
I have been told that to achieve the best performance regarding reduction in sound, the smaller the holes in the baffles are in the moderator relative to bullet diameter the better. So, a 30cal mod on a centrefire .22 in theory won't perform as well as a moderator specifically constructed for that calibre. Would we be able to determine the difference with our ear? I'm not sure.....

I certainly don't think there would be much of a noticeable difference if anything between say a 7-08 rifle using a specific 7mm moderator and then sticking the same model of moderator on but in 30cal format....

No scientific evidence to back this up, just what a couple of rifle builder/gunsmiths have told me.
 
I use the same mod on .17, .222 and .243
its a 6.5mm bore
very quiet on the .243 in comparison to other .243's with non specific calibre bores

the sound reduction is noticeable with closer bore to bullet tolerance but not worth me having 5 mods!
 
The 223 I have just purchased has been fitted with an ASE UTRA SL5 mod for .25 caliber, which according to the ASE suitability chart is "reasonable to use", but not "recommended", as they do a specific .223 model. Without the proper decibel monitoring equipment, it may be that it is difficult to tell the difference.
However, it may be that I have a .25 ASE UTRA SL5 up for sale or swap soon, as I wanted this rifle to be as discreet as possible. Would have kept it for the .243 , but different threads.
 
As has been said sir

your correct, for the best performance of a moderator is to have it as close to the bullet dia as possible, but the fact that you don't have a db meter in your head then its going to make little or no difference to you,

a few years back i did a write up on a few mods for a magazine and i had a few very good moderators and the equipment to test them with results that were correct and not an estimate, and found them to be relatively close to the manufacturer's reading, but don't forget if they don't state the obvious then they could be had up in court if something went wrong, so their reading information and recommendations are a legal requirement enforced on them by law.

i have used in the years gon past a 308 t8 on a 223/243 and a 308, i can still here ok. ...................whats that............... 10 to 4 mate,



bob.
 
I use a ASE Utra S5 on a Tikka .223 and CZ550 .243 via 1/2" UNF thread. Never measured sound reduction. However, very greatly reduced sound and great piece of kit, especially considering the cost of one mod as opposed to two.
Regards
 
ive had a caliber specific mod on 243 but now use the same mod for 308 and 243 no noticeable difference at all
 
i use a t8 br silencer on my 243 i drilled the last baffle to go on my 7mm rem mag with just enughf clearance to let the 7mm out sound reduction from my 7mm is better than the 243 using the same mod so id go for what ever sound moderator isclosest to your bore diamiter
 
a few years back i did a write up on a few mods for a magazine and i had a few very good moderators and the equipment to test them with results that were correct and not an estimate, and found them to be relatively close to the manufacturer's reading bob.


Hi Bob, What magazine was that ?
I'd like to get a copy and as it must have been a shooting magazine I am sure they will have back copies available.
I used a .308 T8 on some of my smaller calibre rifles and I am sure it worked as well, if not better.
My reasoning behind this is that if the volume inside the T8 was built to take into account of the gasses produced by the powder of a .308 then it could, and did, easily 'swallow' the gasses from the .222, 22-25 and .243
 
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The only note of extreme caution in using a moderator closer to the bore of your rifle than 'recommended', is that you need to ensure that your threads are cut in perfect concentricity with the bore. Some aren't.

As it happens, I asked Colin at onelesscharlie the question on drilling out one of his mods to a bigger calibre the other week - he said it was an absolute non-starter on the grounds that you couldn't guarantee that there would be no swarf left by the operation which could cause a problem. I can see his point.... certainly on the more modern close fitting compact mods.

:confused:

​Fizz
 
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