new compensator issue.

[DRichardson]

I have older 38 super shorty open gun. originally it had a full profile steel comp with 3 upward ports that was very heavy. I added a EGW conversion cone with a Cheely 4 port titanium comp. Using the same loads as before (4756 with a 124) now I get distracting fire ball on most shots. I tried a few other load and noticed all seem to have much more flash than before. Is there something with this comp, maybe the much larger more open ports, that causes this? Is there anything I could do short of a different comp to change it. I have always used regular small pistol primers with my 38 super loads and a local guy sugested trying as small riffle or small pistol magnum primer, does that sound like it would help solve this issue if I havent had any other problems?

thanks

[ExtremeShot]

Everyone, and I mean everyone, has their own opinion and observations when it comes to compensator design. I think that having big ports just blows the gas out quicker...where it can't be used anymore. That's why my guns have comps with smaller ports (like in the attached picture). I think the smaller ports hold in the gas more where it can push against the vertical surfaces and reduce felt recoil. My elbows definitely notice the difference. I also don't get a huge ball of flame. So, yeah, I think the difference you are seeing is due to the bigger ports you describe.

D

[j0s3ph]

Everyone, and I mean everyone, has their own opinion and observations when it comes to compensator design. I think that having big ports just blows the gas out quicker...where it can't be used anymore. That's why my guns have comps with smaller ports (like in the attached picture). I think the smaller ports hold in the gas more where it can push against the vertical surfaces and reduce felt recoil. My elbows definitely notice the difference. I also don't get a huge ball of flame. So, yeah, I think the difference you are seeing is due to the bigger ports you describe.

D

Is that a Solidworks Model?

[ExtremeShot]

Is that a Solidworks Model?

Yep.

[Mparker]

I've been testing comps on my 22LR match grade pistols and I'm pretty sure that port size and shape does make a difference. I would expect this is especially true in the larger calibers. Volquartsen makes a number of compensators for 22LR pistols, some are specifically for their custom pistols, others are available for any 22 you'd care to attach them to. They are ported in several patterns (slots, holes, ovals) for reasons I am not fully cognizant of but I am pressing on. The most interesting one to me is the forward blow version.

Two conclusions so far: 1) No pattern helps me be more accurate; 2) More holes seem to soften the recoil better than fewer holes.

Edited November 17, 2013 by Mparker

[Carmine]

I've often wondered regarding the actual science ( not perceived) performance of comps on Open Guns...and for that mater Ported Barrels.

Take into account all the variables....treating it like a science.

Calibre is in my opinion the best place to start......what are you going to shoot 9mm, .38 super ( and its variants)

The uniformaty of the proppelent charge as to give the desired fps has to be established as to give the numbers to continue with the design of the comp.

The bullet itself again uniformaty of all the phyisical parrameters..Wieght, Diameter, the structure of the round itself ( open base or closed) ect.

Then comes the comp and the phyisical layout of the ports themselves...tapered walls, the actual diameter of the bullet path, the bottom of the comp ports. ( flat or rounded)..then the sheer number of ports ( and side ports also) along with the wieght of the comp.

We've all seen guns that have heavy inefficient comps or in calibres that cant generate enough gas to work "corectly"

Now puting it all together ( the NASA boys can do the number crunching). the bullet moving at so many fps, will only have a certian amount of dwell time where it enters the comp and for a fraction of that that dwell time will allow the gasses to venture in the comp ports and generate a thrust as the round is leaving the "first chamber" ( thrust is measued in newton meters or joules of energy)...thus compensating for the lift of the gun in recoil...and yes the recoil cycle is another part of this delicate bit of engeneering.

So is it any wonder that there are almost as many comp styles and layouts as there are open shooters.

Seems to me that there's a whole lot of numbers to be crunched...then again a Stradavarius is hard to replicate with just the number....but you do get closer to the truth once you , as the name sake of this forum says...Maku mozo

Sorry for the crappy text, im fighting a wicked head cold

[DRichardson]

Just to follow up I swapped out the CCG comp to a ECG bob marvel compensator and did some more testing. With the ECG comp the fire ball problem is gone. The ECG comp has much smaller ports than the CCG comp and it noticeably changes the flash signature. With my normal 4756 load there is no flash. With 3n38 which has had a large flash in almost every open gun I have seen it used in is even much less and is only a dull red instead of the very bright white fireworks show. As far as feel goes I think is pretty much a toss up as. The CCG may have been a little softer feeling and I think the ECG flatter but I didn't really put forth any effort in trying to perfect a load for the CCG comp other than trying different powders to seen if the flash problem was across the board.

I would like to see what the difference would be on a full size 9major gun as I'm thinking that would work better for the CCG comp with a smaller charge of powder and longer barrel for it to burn in.

I'm not writing this to endorse either comp as every comp on the market will do the job in the right application. I still would like a more scientific explanation on compensator design and functioning if anyone else has any input.

[OpnGnerr]

I'm running a bedell TI comp and have used or Tries just about every powder that is applicable for 38 sc and from my limited experience with open guns/comps I would say the chambers on the bedell comp are fairly large, but I've never noticed any flash while running the gun, but have been told by fellow shooters while using 3n37 that a massive fireball was flashing even then I didn't notice it from my perspective. I also see other open shooters with a heavy muzzle flash and they never seem to notice, or maybe they do but are adjusted to it. There's just so many combinations of powder, comps, bullets etc i believe it's about finding the right recipe for your particular set up which it sounds like you have done.

[lcs]

I run a full size 9 major with CCG custom comp and 115 with HS6. Folks say the gun "sparks" a little, but I never notice it.

[Carmine]

Well, as long as you like the effect...its all good