Popple holes and minor

[bmiller]

So my open gun slide cracked, and I am in the process of putting a new slide on it.  I will probably in the future put more minor rounds through it shooting 3-gun and falling steel matches than major.  Do popple holes make a difference shooting minor loads?  The loads I run for steel are usually 1250 to 1275 fps, as most matches have a 1300 fps max at their matches.  I use this load in 3 gun as well, shoots flat enough and puts down poppers well.  I have been doing some research and I am thinking about trying a couple 3/16" holes.  Worth while or not?

Edited September 5, 2017 by bmiller

[Hi-Power Jack]

Don't know about popple holes, but the comp on my TruBor makes

9mm Minor loads feel like a cap gun.

 

I'd imagine any kind of gas bleeding system (popple holes) would

have to have some effect.

 

The higher the dose of powder, the more effect - if you're using

a slow powder (7+ grains) that should have enough gas to have

some effect.

 

Don't think I'd spend any money on it, though.   I would imagine

you'd get all the effect you need from the comp, alone.

 

BUT, let's see what the experts have to say ....    

[bmiller]

If my memory is correct, I think I am running 5.8 grains of autocomp for the minor loads.

[Aircooled6racer]

Hello: Don't put any holes in the barrel. Putting holes in the barrel makes it a shorter barrel so you will need more powder to get the same power factor. A well designed comp does more and can also shoot softer. Thanks, Eric

[bmiller]

I was very happy with the gun without holes. I am reusing the barrel, so this would be a relatively cheap experiment.  I am very tempted to skip the holes.  

[Flatland Shooter]

My USPSA Open pistol has both a comp and 4 popple holes.  Runs great at 172 PF.   When I started shooting 3 gun, I used the same gun but with 135 PF loads. (Same powder, N-350, just a smaller charge.)

 

After a while I decided to build a dedicated 3 gun pistol.  The comp is a bit different and it does not have the popple holes.

 

Shooting both guns with the same 135 PF loads I do see less red dot movement on the gun with the holes.  Both guns have a 7# recoil spring installed. I can't say for sure its the holes since the first gun is the one I've shot thousands upon thousands of rounds through it while the second gun that is a dedicated 3 gun pistol has had less than 2000 rds put through it.

 

In my unskilled hands, the popple holes do help.

 

Since it will be an inexpensive experiment, get familiar with the gun and see how it shoots without the holes,  If you want improvement, then add a few holes and see if you feel a difference.  

 

What can it hurt?

 

Bill

Edited September 5, 2017 by Flatland Shooter

[zzt]

My Open gun has two 3/16" poppels and a 3-chamber, 4-port comp.  My backup is the same without poppels.  The gun with poppels shoots decidedly flatter than the backup, at the expense of more noise, and a little harder hit to the hand.  Same load in both.

[bmiller]

8 minutes ago, zzt said:

My Open gun has two 3/16" poppels and a 3-chamber, 4-port comp.  My backup is the same without poppels.  The gun with poppels shoots decidedly flatter than the backup, at the expense of more noise, and a little harder hit to the hand.  Same load in both.

So, in your opinion, are the holes worth the added blast and recoil? 

 

Thanks

[Aircooled6racer]

2 hours ago, zzt said:

My Open gun has two 3/16" poppels and a 3-chamber, 4-port comp.  My backup is the same without poppels.  The gun with poppels shoots decidedly flatter than the backup, at the expense of more noise, and a little harder hit to the hand.  Same load in both.

Hello: If you are using the same load in both you must have a slow barrel in the non holed barrel or you are shooting a higher power factor in that pistol. Adding the holes to a barrel means you need more powder. Up to 0.3 grains more I have seen with two barrels that were shot after the holes. My vote still is for no holes and a good comp. Thanks, Eric

[zzt]

b, I like flatter shooting as long as the dot is well behaved.  While there is more recoil felt in the hand, it is not that much.  Open guns shoot much softer than limited guns, because the gasses push against the baffles in the comp and pull the gun forward.  The barrel ports rob some of that gas, so the comp is mot as effective at mitigating recoil.  However, the diverted gas does push the muzzle down.  I bought both my Open guns used, so I have to live with what they are.  If I shot my backup gun better/faster than the other, I'd be using it instead.

 

I am building two new Open guns, both in 9mm.  One will be a 1911 dedicated to Steel Challenge.  The other a 2011 for USPSA.  Both will start out with Trubore blanks with Eric's custom comp cut into them.  The 1911 will be minor only, so I'm sure it will not need popples.  I don't know about the 2011.  Since comp effectiveness is determined by bullet weight, powder used, and PF (among others)  I'll have to do a lot of experimenting.  I hope to find a combination that works using only the comp.  I don't need it to shoot dead flat.  As long as it returns to the same spot quickly for the second shot, I'll be happy.  If not, I'll put poppels in the comp.

[zzt]

Eric, with the same load the backup gun is less flat.  It is 171PF, the other is 168PF with the same load.  I do have to up the charge by 0.2gr to make up for the holes and get back to 172.  My main gun still shoots flatter with the hotter load.

[bmiller]

I think I'll build it without holes and shoot it.  Holes are easy to add later.