Comp for 9mm pcc

Canuck44 said:
...How much is "big" and how do you know that. ...

The only way you can answer what you are asking ..

FYi Compensators according to Mr. Google ...
Click to expand...

Post #17 in this thread, specific pressure values listed.

You're right that the only way to really know is to do side-by-side testing. For the question of "comp vs. equivalent muzzle weight", apparently nobody here has done that.

It's interesting to consider the history of the compensator (originally for a 10-12" barrel 45ACP SMG, full-auto). I think the "Cutts Compensator" that I have on the shotgun I grew up shooting is actually a brake by the accepted modern definition.
 
AlphaCharlieDelta said:
I've read all the forums you have read Alpining. I was on the fence for a long time on compensators effect in 9mm blowback rifles... Until I did actual real world testing of a few different compensators. ... I can't measure the specifics because I don't have laboratory equipment to specifically measure the amount of muzzle movement, but in real world application it gives me the ability to make a combination of faster and more accurate splits that are measurable in IPSC/USPSA competition shooting.

...99% of competitive shooters at these matches run a comp....
Click to expand...

I'm not sure we have read the same forums. My position is not unusual. I still think the consensus (across many forums) is that there is not sufficient objective evidence supporting the claim that comps work better than an equivalent dead weight attached to the muzzle (for long barrel PCCs). There is a lot of "maybe", and "seems like it should", and "feels like it does", but when it comes to objective info there is more "probably not".

The only real world testing that is relevant to "comp vs. equivalent dead weight" is to actually test a comp vs. an equivalent dead weight. Comparing "with a comp vs. without a comp", or "differences between comps" may be useful information (depending on your methods) but it's not relevant to this specific question. You don't need a lab or anything special, just a shot timer to compare split times on an appropriately difficult target.

You're absolutely right that the top shooters tend to use comps. There are three objective reasons that I can think of: First, on short barrel PCCs, they probably do work as compensators (but this should still be tested rather than assumed). Second, on longer barrel PCCs, they are still are effective as dead weight (as far as I know, there's no better / prettier way to attach dead weight to the muzzle). Third, using a comp makes it easier for the shot timer to pick up the sound of the last shot (especially for long barrel PCCs, because the pressure at the muzzle is so much lower, and thus quieter).

But don't take my word for it - You should ask those competitive shooters for their reasons, instead of assuming that they make the same assumptions that you do. If they do say that their compensator works effectively as a compensator on their long barrel 9mm PCC (I'm sure some do), ask them how they know that it does.
 
Gentlemen, we can agree to disagree. You're convinced based on what you've seen that a compensator works better than an equivalent muzzle weight for a long barreled 9mm PCC. I am not. I am not telling you to take the comp off of your long barrel PCC. As I said earlier in this thread, there are good reasons to have a comp on your long barrel PCC.

Apparently nobody here has actually tried directly comparing "comp vs. equivalent muzzle weight". It's not a purely subjective matter, and it's as easy to test as any other feature you might change on your rifle to improve speed shooting: Compare split times for double taps on an appropriate target, with a comp and with an equivalent muzzle weight.

For anyone deciding for themselves, a quick google search will get you more threads on the topic than you'd ever want to read. I think the Brian Enos forum is one of the best sources, but there are lots of places where you can find good info from serious competition-minded people. If you haven't done so already, think about what constitutes relevant evidence.

From my reading, the consensus seems to be that there is not enough evidence to support the claim that compensators are significantly better for reducing muzzle flip than equivalent muzzle weights on long barrel 9mm PCCs.
 
alpining said:
Gentlemen, we can agree to disagree. You're convinced based on what you've seen that a compensator works better than an equivalent muzzle weight for a long barreled 9mm PCC. I am not. I am not telling you to take the comp off of your long barrel PCC. As I said earlier in this thread, there are good reasons to have a comp on your long barrel PCC.

Apparently nobody here has actually tried directly comparing "comp vs. equivalent muzzle weight". It's not a purely subjective matter, and it's as easy to test as any other feature you might change on your rifle to improve speed shooting: Compare split times for double taps on an appropriate target, with a comp and with an equivalent muzzle weight.

For anyone deciding for themselves, a quick google search will get you more threads on the topic than you'd ever want to read. I think the Brian Enos forum is one of the best sources, but there are lots of places where you can find good info from serious competition-minded people. If you haven't done so already, think about what constitutes relevant evidence.

From my reading, the consensus seems to be that there is not enough evidence to support the claim that compensators are significantly better for reducing muzzle flip than equivalent muzzle weights on long barrel 9mm PCCs.
Click to expand...

From your reading you say. Interesting. Several of us here can do you one better, from our actual experience in shooting our PCC's we know the Comp works.

Now as to adding 3oz to the end of the barrel....why not just add a 3oz bracelet on our support wrist. Alpining I don't have to pee on an electric fence to know it is not a good idea but you are free to try it and tell us if it differs from my assumption that it may not be a bright idea. I look forward to hear how you make out.

ACD suggested you have met the definition of a Troll. After reading his observation I am now convinced you are. The things you learn when you can read.

Take Care

Bob
ps where is my ignore list.
 
Apparently we can't agree to disagree. I'm genuinely sorry to hear it Bob, but that's your prerogative.

From what you've written in this thread, you don't know the comp works. You assume it works. You haven't tested it against a dead weight to determine one way or the other. That's also your prerogative, of course.

But sure, why not add 3oz to your support wrist? Remember when JP used to make and sell handguard weights? And then they stopped, despite them being very popular from my memory... When firmly attached to the firearm, mass helps dampen the recoil impulse. The further towards the muzzle you add it, the more it dampens muzzle rise, specifically. Ever notice that bigger guys handle recoil so much better? And how placing your hand as far forward and high over the forend as you can, you can have a huge effect on muzzle rise? It's not just the effect of muscle resisting movement: It's mass, when firmly attached to the firearm.
 
An easy way to dis/prove Alps theory would be to tape up the ports on your comp and shoot some rounds.
It will then effectively be a dead weight in the same form factor as it is when functional.
I'd be curious to see your results Bob if you are so inclined.
 
GimpyGolden said:
An easy way to dis/prove Alps theory would be to tape up the ports on your comp and shoot some rounds.
It will then effectively be a dead weight in the same form factor as it is when functional.
I'd be curious to see your results Bob if you are so inclined.
Click to expand...

I tried filling in the side ports on my Lockhart Comp/Brake with Epoxy before I bought the TK Comp. After leaving it to harden for 24 hours I went out and put 50 rds down range. All that happened was the Epoxy blew out of the ports even with the top ports open. The top ports on the Lockhart comp/brake are quite small compared to the TK and Davinci designs. I did not spend any more time trying to plug the ports. I have shot both the FX9 10" barreled and Raven9 18.5" with and without the TK Comp and the difference is night and day.

I am of the opinion the comp works best using slower powders. The CFE Pistol Powder is what I used when I did the Chrono work reported previously. As evidenced in the numbers the velocity obtained in both the 10" and 18.5" barrels are virtually identical. To me that is indication the pressure levels had not dropped significantly to affect velocity. We tend to compare velocity changes say between a 4" Handgun and an 18" barreled carbine where we see higher velocities in the longer barrel likely caused by the complete burning of the powder in the longer barrel. In the test I ran the comparison was 10" to 18.5" where I found in my guns that day there was no difference.

I am now working on a pistol load using CFE Pistol that will give me 130PF in my 5" pistols. During the testing I'll see if the velocity levels differ between 10 and 18.5" using less powder. If I find a load that gets me to say 140 in a 5" barrel I'll then try it in the carbines. I don't need 160ish PF which is where I am with 5gr of BDX to shoot PCC Division in IDPA or IPSC. I am frugal and less powder saves me more money. LOL The Comp will have to continue to work and lower powder charges. Recoil iis not lessoned by the Comp I am using just muzzle rise and that is more important to me then achieving less recoil. The 9MM is not hurtful when it comes to recoil.

Take Care

Bob

PS the testing I will be doing is not going to happen soon but once done I'll open up another thread and report my results. Remember whatever the results they will be on one gun on one day at 200' above sea level. If you are shooting in Calgary your results will be different ie velocity will be greater using the same amount of powder.
 
Canuck44 said:
I am of the opinion the comp works best using slower powders. The CFE Pistol Powder is what I used when I did the Chrono work reported previously. As evidenced in the numbers the velocity obtained in both the 10" and 18.5" barrels are virtually identical. To me that is indication the pressure levels had not dropped significantly to affect velocity. We tend to compare velocity changes say between a 4" Handgun and an 18" barreled carbine where we see higher velocities in the longer barrel likely caused by the complete burning of the powder in the longer barrel. In the test I ran the comparison was 10" to 18.5" where I found in my guns that day there was no difference.
Click to expand...

I was under the same impression myself, as shooting all different division in IPSC over 30 years. Those were the pistol conclusions that I came to, for open guns. Use the lightest allowed projectile and the slowest powder to get maximum gasses to make the comp work, whereas non-comed guns, the heaver projectile and faster burning powder.

I used this principal when developing a load for my 10" and 18.6" barrels that are comped. I found that the 18.6" barrel ran about 8-10 fps faster, not a noticabled difference.

What what was suprising when I was devekoping the load, and used a benchmark or 133 pf. Using various burn rate powders, from fastest to slowest N310, Titegroup and N350 (my open gun powder). I found a comp on a PCC worked better with a light projectile and a fast burning powder.

This link is me testing the 3 powders with a loose grip to allow for the muzzle to flip with minimum restriction. https://www.facebook.com/share/p/ZxfYpdEkV6jEoyUn/

As you can see the fast powder with the light projectile gave the lowest muzzle flip, and softest backward recoil. All 3 tested loads were at 1100 fps with a 121 RNHB Campro projectile.

So if you are trying to see if a barrel weight will work as well as a comp, I can say with 100% certinity that a comp will definatelly outpreform it, as you are adding the extra energy from the gasses pushing the barrel downward, whereas a weight will only have the effect of gravity on the weight.
 
GimpyGolden said:
An easy way to dis/prove Alps theory ....
Click to expand...

Thank you, but it's not my theory (I know that's not what you meant, Gimpy :d): It's my reading of dozens of threads on the topic over several years, contributed to by probably hundreds of people. No single test or report will be definitive and generalizable, regardless of the results one way or the other. I encourage anyone interested in the topic to do their own search. It's not hard to find info, just be prepared for a lot of noise on the subject.

I can't speak for Bob, only read what he's written. He's given loads of detail in this thread about why he is comfortable with his assumptions, and it doesn't look like he is going to revisit the subject with any direct testing. Nor should he, if he's satisfied with where he's at. Nor would anyone, who is satisfied with his detailed explanation (or their own explanation, if they have different reasons). I'm not satisfied: I think that if you want to say that "A" is better than "B", then you actually have to try both "A" and "B".

Toxic had an idea earlier in this thread to try shooting the rifle with the comp indexed upside down. Interesting idea, for sure. I'm no physicist or engineer, but my gut says that that method would be more subject to inconsistencies and problems arising from grip. But at least it would be something relevant to the comp vs. muzzle weight question than additional repetitions of "flatter with a comp than with no comp", and "flatter with comp X than with comp Y".

IMO (if anybody cares :yingyang:), for shooters on the range, the best test of comp vs muzzle weight is to compare split times for double taps on a "just right" target (the right size and distance). With a long-barrel 9mm PCC, compare a comp with an equivalent dead weight attached to the muzzle, using a consistent real-world shooting grips and positions. Repeat the test enough times to try to reduce the average error due to inconsistent grip, and the law of averages should catch up with you and clean up the data. IMO, this will give better (cleaner and more realistic) data than trying to achieve a repeatable "loose grip", (which is what you see done when the tester is trying to maximize muzzle rise). Either there is a measurable difference or there is not.
 
Canuck44 said:
...I am of the opinion the comp works best using slower powders. ...

As evidenced in the numbers the velocity obtained in both the 10" and 18.5" barrels are virtually identical. To me that is indication the pressure levels had not dropped significantly to affect velocity. ...
Click to expand...

Just in case we are still talking, Bob :d, I think you're absolutely right about comps working best with slower powders. It's been well established over the years. I think there must be something else going on with madcow's results - It would be interesting to see his tests repeated with a different rifle, and/or a different shooter.

Generally speaking, all things being equal, one of the things we can be sure of is that the pressure at the muzzle is always going to be less with a longer barrel. If you don't accept Toxic's pressure numbers from earlier in the thread, you can easily obtain your own pressure information from Quickload or Gordon's Reloading Tool.

Your assumptions may be incorrect, and there's an easy way to test for yourself (if you want to).
 
madcow said:
...Those were the pistol conclusions that I came to, for open guns. Use the lightest allowed projectile and the slowest powder to get maximum gasses to make the comp work, whereas non-comed guns, the heaver projectile and faster burning powder.... I found a comp on a PCC worked better with a light projectile and a fast burning powder. ...

So if you are trying to see if a barrel weight will work as well as a comp, I can say with 100% certinity that a comp will definatelly outpreform it, as you are adding the extra energy from the gasses pushing the barrel downward, whereas a weight will only have the effect of gravity on the weight.
Click to expand...

I thought your findings re: projectile weight and powder burn rate were very interesting. I suspect there is something else going on with your results. Maybe it's just that rifles are different animals from handguns. Maybe the difference in action type (straight blowback does have a different recoil impulse), maybe the difference in the shooter's grip compared to handgun, maybe something else?

Maybe, it could be the case that even with the 10" PCC that you showed in the videos, there's not enough gas at the muzzle to make the compensator work very well as a compensator. So maybe the differences you're seeing in recoil and muzzle rise are more due to the differences in recoil impulse that you get from different powder/bullet pairings, than they are differences from how the powder/bullet pairings are gassing the compensator. Heck, maybe that accounts for all of the observable difference.

You sound very certain that comps work better than equivalent muzzle weights, regardless of barrel length. What are you basing this on? Have you tried comparing a compensator to an equivalent dead weight attached to the muzzle of a long barrel 9mm PCC?

You're absolutely right that as long as a comp is attached, there is going to be some energy from escaping gases pushing the muzzle downward. The question is whether there is enough energy to make a measurable difference at any given barrel length.

Despite joemanco's gentlemanly attempt at diplomacy earlier (thank you for trying to make CGN a better place :d), for any given rifle/ammunition/shooter combination, it either makes a measurable difference or it doesn't. Nobody here (including me) has indicated that they've even tried making a direct comparison between a compensator and a muzzle weight, so I'm surprised at the degree of certainty in some posts.

madcow said:
Its a custom made one we designed here in alberta
Click to expand...

Do you sell these comps? I've been looking for a good muzzle weight, and I buy domestic whenever I can.
 
edgy said:
I believe he has them listed on GP
Click to expand...

Looks like they are here on the EE, too. Good for him, it looks like a business venture and I hope he does well.

Maybe he can clear the air, since he was actually involved in the design of a compensator: How did they determine that there is enough energy from expanding gas at the muzzle of a long barrel 9mm PCC for the compensator to have a measurable and significant effect as a compensator (more than an equivalent dead weight)?

On an unrelated note, for those people interested in PCC accessories that have unmeasurable and/or insignificant effects on long barrel 9mm PCCs, I have some brand-new Compensator Intensifiers ® available for purchase. They stick right on to your existing comp. They look a lot like the gold star stickers that elementary school teachers aren't allowed to give out anymore - But don't be fooled, these will make your existing compensator even more compensatory.
 
we are current in process on our next batch of the comps. This comp is being quite popular in the PCC circles

The only thing I can account for the fast powder/light projectile for the PCC versus the Slow powder/light projectile conclusion is most likely the power factor I was trying to attain.

For hangun, I was looking for a Major PF of 173 which is much more gasses involed versus the Minor PF of 133. Power factor is calculated by weight of projectile multiplied by velocity divided by 1000 for IPSC for those that may not know.

video results

Fast burn rate
Medium burn rate
Slow burn rate

you be the judge which burn rate seems to work better. 100% compensator works

PS This rifle has the Short Stroke Kynshot buffer system in it so rour resulst may slightly differ
 
Last edited:
madcow said:
we are current in process on our next batch of the comps. This comp is being quite popular in the PCC circles

The only thing I can account for the fast powder/light projectile for the PCC versus the Slow powder/light projectile conclusion is most likely the power factor I was trying to attain.

For handgun, I was looking for a Major PF of 173 which is much more gasses involed versus the Minor PF of 133. Power factor is calculated by weight of projectile multiplied by velocity divided by 1000 for IPSC for those that may not know.

video results

Fast burn rate
Medium burn rate
Slow burn rate

you be the judge which burn rate seems to work better. 100% compensator works

PS This rifle has the Short Stroke Kynshot buffer system in it so rour resulst may slightly differ
Click to expand...

Thanks for this. Saves me hanging my 3oz.watch on the end of my Raven9's barrel. :>)

FYI I am currently running 4.7 gr of CFE Pistol under 124 gr BDX FMJ with good results.

When do you anticipate the arrival date for your Comp and and what approx. price point?

Take Care

Bob
 
madcow said:
we are current in process on our next batch of the comps. This comp is being quite popular in the PCC circles

The only thing I can account for the fast powder/light projectile for the PCC versus the Slow powder/light projectile conclusion is most likely the power factor I was trying to attain....
Click to expand...

Glad to hear your business is growing.

Agreed, your results are unexpected. Maybe your PF goal was the cause, but I'm not sure how that would affect things. It's also possible that there was just not enough gas and gas pressure at the comp for the powder/projectile combinations to have the expected result. It would be easy to rule this out, by trying the same test with an equivalent weight attached to the muzzle instead of the comp.
 
madcow said:
.... 100% compensator works...
Click to expand...

You've got more experience than anyone in this thread with compensator design, so your input is very valuable. I'm sure you want your customers to know what your comp can and can't do for them, especially on a non-restricted 9mm PCC (I'm guessing that's 99% of Canadian PCC owners).

Each time that you have said your compensator works (better than a dead weight at the muzzle), you have made no mention of barrel length. Is there a barrel length that is too long for a compensator to have a measurable and significant effect as a compensator? A point at which it effectively becomes a dead weight?
 
You must log in or register to reply here.
Back
Top Bottom