Over sizing moderator gauge to safeguard from clipping

[Mackie]

I’m considering a moderator for my stock PROD.

I read in another thread about upsizing gauge (.25 vs. 22 caliber opening). Maybe avert clipping on accidental double load?

Does this somewhat defeat the moderator effectiveness?

Can you remove the PROD fill cap with a cone adapter? Considering a DonnyFL Tanto.



Thanks.

 

[scottblair]

Enlarging the exit hole one caliber size will slightly increase the sound level, but hardly even noticable. I've done it many times.

Well worth it to avoid potential clipping, imho

Scott

 

[davecole]

I order my moderators for the next caliber size up. Kinda curbs the clipping potential. 

 

[rangur1]

i also moved to the one size larger with my mods to ensure minimal risk of pellet clipping.

 

[STO]

It is worth noting that different designs lean more heavily on exit OD for sound attenuation than others. It really depends on how the given moderator is designed. Also, your propensity for clipping increases the further away from the end of the gun barrel is, so potentially reaming different baffles to different diameters depending on how far from the muzzle they are may give you optimum performance. 



As an aside, the closer the pellet travels to the silencer's internals, the stronger the aerodynamic interaction. You can get substantial POI shift without any physical clipping. Larger bore IDs help minimize this, which is why, all else being equal, you'll tend to get better accuracy from larger bore moderators. 


Just my 2c.  

 

[Bruce54]

Donny FL shows an adapter that just screws on to the end of shroud (using same threads as original end cap) and has1/2 x 20 thrd for moderator. He makes for m-rod and p-rod both.

 

[John "spysir" Blount]

I like then tight, just me. You could loose the shroud and slip on a TKO. Huge improvement over stock. Opening up the holes in the barrel "stripper" and adding a 1/4" id washer makes a great difference over stock, that and the entire shroud forward makes ours as quite as the hammer strike can be.

John

 

[jwrabbit123]

I got like 5 donny fl and I learned , if the moderators are mounted to barrels and threads true yes you can use same size , but . on a lower line gun or a gun which everything is not straight and plumb then yes I now would get a bigger size

I had a problem 1 time on Hatsan where the moderator was mounted to the shroud and it clipped the moderator .so any tube must be perfectly straight and aligned to barrel , I found you don't increase much by going a bigger size anyways . actually Donny told me this .and I do this now to prevent problems

LOU

 

[airgunfans]

I have been wondering why all commercial moderators are designed to have just one-point support at the end of the shroud. Unless the thread there is sufficiently long and the fitting is tight, chances are there that the moderator may not line up well with the shroud. All my DIY moderators have an additional slip-on support point achieved by extending the outer case of the moderator backward covering up 2 ~ 3 inches of the shroud. Besides achieving better alignment, the arrangement also creates additional volume of the "blast chamber" that may help to suppress the sound level further.

 

[stoti]

When I bought my first DonnyFl moderator I remember Centercut telling me to order the .25cal. to use with my .22 cal. Airgun. I didn’t, I thought I knew better and wanted it as quiet as can be. I was wrong, Centercut was right. The pellets clipped occasionally for no apparent reason and I ended up boring out the moderator. The difference in report is negligible, so save yourself the trouble and upsize one caliber. All these guys giving you advice to do so know what they’re talking about!

Stoti 

 

[bucketboy]

I have a simple way to check if the mod is on square. After fixing, stick a piece of insulation tape over the exit hole of the mod, take a shot and inspect the pellet hole is plum centre to the exit hole.



Bb

 

[STO]

I have a simple way to check if the mod is on square. After fixing, stick a piece of insulation tape over the exit hole of the mod, take a shot and inspect the pellet hole is plum centre to the exit hole.



Bb

^this dude knows what's up. I do this all the time when checking experimental moderators although I use masking tape. +1 to you sir.