Popple holes ?

[cecil]

I am considering a new open gun as my main shooter... will be 9mm to shoot open major.. probably 6.8 grs Auto Comp using 124gr Precision Delta HP bullets.. SP primers which makes 171 PF in my present STI with 5" barrel & titanium comp... I am undecided if I should get popple/barrel holes and would like to get some feedback to help me make my decision... I am presently a C class shooter ..

would like to get some opinions if popple/barrel holes can improve accuracy.. my first shot is usually good, but the second one is not always ..I find that the dot moves considerably after the first shot..

tia

[kneelingatlas]

It sounds like you have an issue with technique you're hoping the equipment can fix.

You can only shoot the second shot as fast as you see the dot on target again.

A flatter gun can help, have you tried 115s?

Here are my thoughts: you're using a full sized gun with a small powder charge of a fast powder and a heavy bullet (obviously all relative terms) so you're on the soft side of the soft/flippy vs violent/flat side of the spectrum. You can certainly move the gun you have down the spectrum with lighter bullets and slower powder to see how you like it before you commit to a new build.

Edited December 31, 2014 by kneelingatlas

[shooter.860]

I have a similar gun with same bullets but using 7.1 grains of Autocomp. 173 PF

Have you tried upping your charge weight ?

My gun is pretty flat shooting, people say it moves about a 1/2 inch or less.

I agree that technique would help with 2nd shot.

You got to shoot often and figure out what works and what doesn't. I practice on partials as it forces me to really see that 2nd shot

Edited December 31, 2014 by shooter.860

[calvinc78]

Popple holes will help flatten it out but it's not going to make a world of difference. If your having issues with the second shot just adding holes won't fix that nor will it raise your class. Range time and dry fire....

[Hi-Power Jack]

C class shooter ..

if popple/barrel holes can improve accuracy

Tia, I'm a B OPEN shooter with a TruBor 9mm major,

and popple holes might help me, but I believe I have

other issues holding me back which are more important

than popple holes.

I'm also using 124 gr bullets/6.8 gr WAC - and I'm going

to play with 115's and HS6, and higher PF's to see if

that might help the dot stay flatter, BUT, I'm not sure

that is really anywhere near a significant issue with

me progressing, at this point.

I have to agree with the other people who responded. :bow:

It's worth playing with, I guess, but dry fire and practice

will probably advance your ability a lot more than

popple holes.

[Aircooled6racer]

Hello: No popple holes if the comp is a good design. What gun are you shooting now. Sounds like you need to tune the gun to suit you. Changing springs, PF, bullet weight and changing the firing pin stop contour can do a lot. Thanks, Eric

[cecil]

I am shooting an STI with a 5" barrel that is compensated . trigger breaks at 2-1/4lb ...its a second hand gun... 6.8 Auto Comp powder -- 17lb main spring... thought Auto Comp was a pretty slow burning powder .. pushing 124 gr Precision Delta bullets.. chrono-ed 171 PF last time I checked ...

there are no markings on the compensator to identify what brand..

what brand of compensator would you recommend ????

tia

Edited December 31, 2014 by cecil

[lcs]

If you have a local smith that can do the work, have 3 popple holes. If you have to overnight your gun, wait for a lot of work.

Popple holes help--not the Holy Grail. I currently have 5 and I'm shooting 115s with HS6. Why did I say 3 holes when I'm configured for 5--Easy answer--- I had 3 at first and shot numerous matches-I then added 2 more holes. The extra two holes did nothing in my opinion.

In the end...only you can determine if the holes were worth it.

[kneelingatlas]

thought Auto Comp was a pretty slow burning powder

http://www.hodgdon.com

Check out the burn rate chart, Autocomp and Silhouette are the fastest of the popular powders, HS6 and 3N37 are in the middle, with 3N38 and N105 being the slowest powders suitable for major in a 9mm. Your barrel sounds fast so you might make major with N105 unless you start drilling holes in it

Posting a picture of your comp is probably the best place to start. You dont want to start drilling holes when you could just switch comps and be much happier.

But like I said earlier, if you take note of where the dot is when you break the second shot those groups will tighten up right away. There are plenty of SS shooters ripping pairs of alphas in a hurry using 45s with no comps, so its not the gun

[cecil]

I looked up HS-6 & Auto Comp... they are almost identical in burn rates.....

. i am not so naïve to think popple holes would jump me from C class shooter to B class shooter... i just attempted to get some feedback to see if popple holes were an attribute or just farkel... .. i think just about everyone here would try something that would improve their shooting just a tad..

thanks for all the help !

[kneelingatlas]

You know I just read that burn rate and its way different than their last one and at least with the powders we're talking about it's not consistent with my data.

With 115s it takes me 7.2gr to make major w/ Autocomp and 8.6gr of HS6.

Edited December 31, 2014 by kneelingatlas

[New Old Guy]

can you use a faster powder like VV N320 with 115gr bullets in an Open Gun? (assuming that's all I can get)

[Shadyscott999]

First...IMO, unless you have a complete hunk of trash, you can make A class with anything. Me getting a new gun (build EXACTLY how I wanted it) pushed me over the top to M.

Regarding popple holes, I wouldn't shoot a gun without them. When done correctly, they make a good gun better.

[Aircooled6racer]

Hello: Here is what I would try first. I would get some 115grain bullets and use 7.3 grains of Auto Comp and 1.170" OAL. I would also install a ISMI 8 lb recoil spring with your 17lb mainspring. Try that combo and see how it works for you. Remember Max made it to GM with a Tru Bor. Thanks, Eric

[cecil]

I understand.... but.. how many people do you know that shoot near as well as MAX ??

Edited January 1, 2015 by cecil

[Shadow]

Max used two popple holes.

[robb315]

I understand.... but.. how many people do you know that shoot near as well as MAX ??

EG

[lcs]

can you use a faster powder like VV N320 with 115gr bullets in an Open Gun? (assuming that's all I can get)

I suppose you could, but fast powders are designed to burn fast and not produce a lot of gas. The more gas, the better the comp works. I would bet getting to major PF with N320 and 115 would probably create excessive pressure and risk blowing up you gun.

Stay with known powder and bullet combinations!

[kneelingatlas]

can you use a faster powder like VV N320 with 115gr bullets in an Open Gun? (assuming that's all I can get)

I suppose you could, but fast powders are designed to burn fast and not produce a lot of gas. The more gas, the better the comp works. I would bet getting to major PF with N320 and 115 would probably create excessive pressure and risk blowing up you gun.

Stay with known powder and bullet combinations!

320 would probably show excessively flat primers before reaching major, but I've never done it so I could be wrong...

Regardless, the comp would do little if anything to mitigate muzzle flip, which really is the point.

Edited January 1, 2015 by kneelingatlas

[Nimitz]

as kneelingatlas first mentioned, it sounds like you are trying to make an equipment change to address a fundamentals technique issue. you can do all the tinkering folks have suggested, even adding popple holes as some believe they are valuable. However, if it were me i would take the money i was planning to invest in a new build an instead invest in a bunch of ammo, take a lesson from a top instructor every 6 months and setup a structured dry fire/live fire program and see where i was after 1 year of dedicated training. My guess is that you would easily be B class if not A with the equipment you have now .... just my 2 cents ...