Making the comp work?

[jbultman]

Hey all, Just recently purchased my first open gun. I've been shooting 40s&w 2011s in limited and reloading for quite a while, 5+ years. But, after doing some research I have a question when it comes to physically shooting the open gun and tracking the dot. For reference I've got a full size 9mm major gun with 4 holes drilled, 2 popples and 2 vee-ports at a 45 deg, in the barrel and a Bedell Ti comp...

 

1) I have yet to decide a powder, I have some CFE laying around, but thinking HS-6 vs AA7. Anyway, what would be a good power factor to shoot towards to make the comp work? As loading for a open gun and non-comp gun seem different. In limited I would load to 170 and call it a day but, what about open? Is there a power factor that makes the comp work better, i.e. 176-180 or is it similar to loading for limited?

2) When I narrow down a powder and load up some rounds, what am I looking for the dot to do? How much movement? What kind of movement? 

3) When i get everything situated, I'm assuming spring wise its similar to finding a proper spring weight in my limited guns? 

 

THANKS in advance! 

J

 

Ohh, and if  this should go in the reloading form, mods I apologize and please move. Thanks.

[aandabooks]

I load with HS-6.  I found CFE/Autocomp to be a little too fast a powder.  Also used to run 115gr bullets but the last few months have switched to 124gr.  Gun cycles just as fast but doesn't feel as violent.  I run my loads between 172-175PF and in videos almost all the gas is going up and very little is going out the front of the comp.  

 

You will be looking for the dot to track straight up and down with a return to center after one bounce.  I don't like it when my dot runs at a diagonal.  It is usually not the powder or load but I need to pay more attention to my grip when that happens.

 

You'll just have to play with springs to figure out what you like.  I run a 9mm in my Czechmate but I've heard others prefer a pound lower or higher.  Get about a 4lb range of springs 8-11lb and see what works for you.

[KellyB]

1. I think each gun has its own sweet spot of pf. For chrono sake it’s best to be 170 & up. You never know when environmental conditions will knock you down a few pf at the chrono table. I like about 171-172 for mine. Over 175 is too hot IMO.

2. Dot movement depends on the dot mechanics also. Typically if you can get it to go straight up & snap back to on target quickly, that is ideal. Some say they have a shimmy shimmy to the left/right. I do not.

3. Spring: ask gun maker what lb & brand. Work from there. Depends on size of gun also.

Welcome to the dark side.

[Hiroshi]

For me, the sweet spot is 174 pf..

[Hi-Power Jack]

I'd load up 50 each of PF 170, 173, 176 and 179  -  try them

and see what feels best to You, in Your gun.     

[zzt]

The PF of your load is irrelevant as long as it consistently makes major.  You have four holes in your barrel that will bleed off a lot of gas before it reaches the comp.  That means you will need even more gas generated to 'work' the comp.  That may be impossible to do with 115gr bullets, given the limited case capacity.  You may be stuck using 124s and you'll have to live with the recoil.

 

He is how I approached working up my 9mm Open major load.  I had been using WAC and Silhouette in my 40 Open loads, and they hit my hard harder than they should have.  Also, the muzzle rose more than I wished.  The reason is the two 3/16" poppels robbed the comp of gas.  I switched from 7.3gr Silhouette to 10.2gr Major Pistol and the results were terrific.  The larger powder charge generated enough gas to work both the poppels and the comp, so the gun shot softer and flatter.

 

Knowing that I started with MP in 9mm.  10.2gr under a 115 HAP gives me 168PF with an SD of 4.  It shot soft, but again the muzzle rose more than I had hoped for.  I added two 3/16" poppels in a V2 and it flattened out, but at the expense of additional recoil to the hand (robbed the comp).  I don't want to go to 124s, so I'll live with it.

 

The rules for making a soft shooting load is to generate enough gas so that all the ports (baffles) of the comp are working, but there is almost no gas jetting out the front.  Jetting out the front increases recoil.  So does not having enough gas.  Gas hitting the comp baffles pulls the gun forward.  That's why you want all of them to work.

 

I'd start your development with either AA7 or Major pistol.  If you can't get enough in the case to make major with a 115, go to a 121 or 124.

[Jamese35]

I'm in the same boat, as I'm starting in open soon. My question is what's the advantage of having a 3 port comp with a few pople holes versus having a comp with more ports?

[jbultman]

The holes in the barrel is the one thing I wasn’t happy with when I purchased from the previous owner. 

I was going to shoot it for a while and see what I can get it to do, then replace the barrel and comp if I’m not happy... I mean after all it’s my fun gun, I’m happy in limited. 

AA7 is what I’m leaning towards. Thinking with the holes in the barrels I’ll have to go with 124s

Sounds like find the 170pf load and increase from there until the gun runs flat and the dot tracks up and down, with the dot quickly returning back to the target.

Take video and make sure all the gas is coming out of the ports and comp not front.

 

Am I correct in my thinking?

[zzt]

3 hours ago, jbultman said:

Am I correct in my thinking?

 

Don't use video.  Use the Brazos test.  I gave you the link in another thread.

[Sarge]

15 hours ago, jbultman said:

Hey all, Just recently purchased my first open gun. I've been shooting 40s&w 2011s in limited and reloading for quite a while, 5+ years. But, after doing some research I have a question when it comes to physically shooting the open gun and tracking the dot. For reference I've got a full size 9mm major gun with 4 holes drilled, 2 popples and 2 vee-ports at a 45 deg, in the barrel and a Bedell Ti comp...

 

1) I have yet to decide a powder, I have some CFE laying around, but thinking HS-6 vs AA7. Anyway, what would be a good power factor to shoot towards to make the comp work? As loading for a open gun and non-comp gun seem different. In limited I would load to 170 and call it a day but, what about open? Is there a power factor that makes the comp work better, i.e. 176-180 or is it similar to loading for limited?

2) When I narrow down a powder and load up some rounds, what am I looking for the dot to do? How much movement? What kind of movement? 

3) When i get everything situated, I'm assuming spring wise its similar to finding a proper spring weight in my limited guns? 

 

THANKS in advance! 

J

 

Ohh, and if  this should go in the reloading form, mods I apologize and please move. Thanks.

Seems like you have gotten some pretty good info here. I'll add that there is no way to know pf without testing. Some guns are nice and flat at 172 while others are flatter at 179. It just depends on your gun set up. With all of those holes I would first experiment with 121's or 124's. You'll probably settle on an 8# recoil spring but it's smart to test at least a 7 and a 9. Open gun load development can get pretty tedious because you are trying so many different things at first. Every load you make you should chrono first, then shoot with different spring weights, etc. Subtle differences are pretty hard to detect but you will definitely know when one load is significantly different from a "bad" load. 

 

I'm around if you ever want to hit the range and work on things.

[jbultman]

1 hour ago, Sarge said:

Seems like you have gotten some pretty good info here. I'll add that there is no way to know pf without testing. Some guns are nice and flat at 172 while others are flatter at 179. It just depends on your gun set up. With all of those holes I would first experiment with 121's or 124's. You'll probably settle on an 8# recoil spring but it's smart to test at least a 7 and a 9. Open gun load development can get pretty tedious because you are trying so many different things at first. Every load you make you should chrono first, then shoot with different spring weights, etc. Subtle differences are pretty hard to detect but you will definitely know when one load is significantly different from a "bad" load. 

 

I'm around if you ever want to hit the range and work on things.

 

Thanks guys,

This is what I'm currently working with....

Thinking I'm going to go with either RMR JHP or PD JHP both in 124gr and load to 1.165" OAL but, I need to check to barrel to see how long I can load.

Thinking I'm going to with AA7, if I can find it local, because its going to require more powder thus more gas and start at a safe amount, 8gr ,and work up from there. Assuming I'm going to be in the 9.5-9.8 grain range. Looking for pressure signs obviously. But, I might as well pick up some HS-6 as well too and test. Thinking I'll be in the 8.2 gr range for that one.

 

Sarge, I'm hoping to start load testing the beginning of the month and the goal is to shoot the last 4-5ish, matches in open, monster matches included. I will try this myself but, When I start having issues I'll hit you up and take you up on your offer! Thanks

 

[zzt]

It's a shame you have so many poppels.  The four baffles in that comp will do fine if you make enough gas to get to them.  After you have experimented for a while and know what you can get, you may consider having a gunsmith thread and pug the V2s.  You can definitely make major with a 115 and two 3/16" poppels.

[jnkill]

115 pd hp, 10.7 of AA7 oal 1.165 makes 173 pf in my axiom ethos, no popper holes

Edited August 19, 2019 by jnkill

[36873687]

1 hour ago, jnkill said:

115 pd hp, 10.7 of AA7 oal 1.165 makes 173 pf in my axiom ethos, no popper holes

When I shot 115 this was close to my load. Awesome combo

[bigboy69]

On 8/17/2019 at 11:10 PM, aandabooks said:

I load with HS-6.  I found CFE/Autocomp to be a little too fast a powder.  Also used to run 115gr bullets but the last few months have switched to 124gr.  Gun cycles just as fast but doesn't feel as violent.  I run my loads between 172-175PF and in videos almost all the gas is going up and very little is going out the front of the comp.  

 

You will be looking for the dot to track straight up and down with a return to center after one bounce.  I don't like it when my dot runs at a diagonal.  It is usually not the powder or load but I need to pay more attention to my grip when that happens.

 

You'll just have to play with springs to figure out what you like.  I run a 9mm in my Czechmate but I've heard others prefer a pound lower or higher.  Get about a 4lb range of springs 8-11lb and see what works for you.

 

HS-6 is faster than WAC or CFE Pistol. 

 

43. HS6

44. WAC

45. CFE Pistol

I think HS6 is not as harsh in the hand as the other 2, but it is a faster powder, but not by much.

[zzt]

1 hour ago, bigboy69 said:

HS-6 is faster than WAC or CFE Pistol. 

 

NO, it isn't.  That powder chart is wrong.  HS-6 takes 1 gr more powder to make the same PF as CFE and WAC.  It is definitely slower.

[bigboy69]

I'm just going by what the burn rates show. I think 2 of them below dont have the CFE pistol on it.

 

Edited August 21, 2019 by bigboy69

[Hi-Power Jack]

5 hours ago, zzt said:

 

  HS-6 takes 1 gr more powder to make the same PF as CFE and WAC.   

 

That's for sure ….    

[Dan4147]

On 8/17/2019 at 10:16 PM, jbultman said:

Hey all, Just recently purchased my first open gun. I've been shooting 40s&w 2011s in limited and reloading for quite a while, 5+ years. But, after doing some research I have a question when it comes to physically shooting the open gun and tracking the dot. For reference I've got a full size 9mm major gun with 4 holes drilled, 2 popples and 2 vee-ports at a 45 deg, in the barrel and a Bedell Ti comp...

 

1) I have yet to decide a powder, I have some CFE laying around, but thinking HS-6 vs AA7. Anyway, what would be a good power factor to shoot towards to make the comp work? As loading for a open gun and non-comp gun seem different. In limited I would load to 170 and call it a day but, what about open? Is there a power factor that makes the comp work better, i.e. 176-180 or is it similar to loading for limited?

2) When I narrow down a powder and load up some rounds, what am I looking for the dot to do? How much movement? What kind of movement? 

3) When i get everything situated, I'm assuming spring wise its similar to finding a proper spring weight in my limited guns? 

 

THANKS in advance! 

J

 

Ohh, and if  this should go in the reloading form, mods I apologize and please move. Thanks.

 

Good info for you on all the replies.  I am not an expert, so I have relied on the shoot white cardboard test for comp/load efficiency.  Load up a bunch of major pf samples, put the muzzle about 1 inch from the cardboard, fire samples.  You will see an impression of how the comp is working with the different loads.  It is easy to see which puts the least gas out the muzzle.  Then settle on the dot performance you like.

[zzt]

18 hours ago, bigboy69 said:

I'm just going by what the burn rates show. I think 2 of them below dont have the CFE pistol on it.

 

You simply cannot trust burn rate charts.  None of them agree, and the testing method does not match what happens in the chamber.

 

The number one basic rule for pistol (and other) powders is slower powders require more charge weight to reach the same velocity as a fast powder.

 

As an example, in one of my Open guns  I require 7.2gr WAC, 7.3gr Silhouette and 8.3gr HS-6 to make 172PF.  It takes 10.2gr Major Pistol to make 168PF.  So clearly the progression from fast to slow is WAC, Silhouette, HS-6, MP.

[Nevadazielmeister]

On 8/18/2019 at 1:37 PM, jbultman said:

 

Thanks guys,

This is what I'm currently working with....

Thinking I'm going to go with either RMR JHP or PD JHP both in 124gr and load to 1.165" OAL but, I need to check to barrel to see how long I can load.

Thinking I'm going to with AA7, if I can find it local, because its going to require more powder thus more gas and start at a safe amount, 8gr ,and work up from there. Assuming I'm going to be in the 9.5-9.8 grain range. Looking for pressure signs obviously. But, I might as well pick up some HS-6 as well too and test. Thinking I'll be in the 8.2 gr range for that one.

 

I would recommend looking at the software called Quickload. https://www.neconos.com/details3.htm

 

My father and I have used this software for 15+ years and have more than saved the $150.00 in powder and bullets. If you REALLY want to know about your load and internal ballistics of your firearm, this is the software to get. The biggest thing I like about it is the percentage powder burned. This is very helpful for open guns since I still want powder burning after the bullet leaves the barrel, to allow expanding gasses to reduce muzzle flip. In the alternative, if I am shooting production, I would ensure powder burn was close to 90-95%. In both instances, I was able to tune my loads to have the least amount recoil. Everything else is make even more wild guesses. 

 

This is just ONE of the many factors you can look into.

[moverfive]

A few of things to note here:

 

burn rate of the powder is the most important thing here.  If you are shooting 9’s, then know your options are very limited.  Just because you see smoke being pushed up through a comp doesn’t mean the comp is getting proper gas to work effectively.  In the super calibers, HS6, autocomp, and similar powders are too fast in my opinion. Need to look at AA7, N105, or 3N38.  With 9’s.....would recommend AA7.

 

There is a difference between popple holes and hybrid holes. Popple holes are small and hybrids are around 3/16 or just under.   When hybrid holes first entered the scene in the early 90’s (we used 4 initially), they only lowered bullet speed by around 50fps.   So the barrel holes have minimal impact on bullet speed (when up to two tenths of a grain of powder will replace that speed) and don’t impact recoil much either.  But the real advantage of the holes was giving the dot a truer up and down movement.  Shortly after their introduction, most realized 4 holes were too many. That is why you see 3 hybrid holes as more common today.....and 4 with popple holes.  Now with barrel profiles changing, as with Barsto, AND still using super.....being forced to 2 hybrid holes.  Things are constantly changing. 

 

And as Sarge stated - the vast majority will find 8lb Springs optimal and will settle on one of two PF sweet spots (172-173 or around 176).  There are always outliers, and I am one of them as one of my guns prefers 178pf with AA7.  As for springs, would heavily recommend Springco or ISMI.   With Wolff springs, you don’t always know if the spring in the package comes close to it packaging label.

[gianmarko]

loads will have to be chronoed and tested, period.

 

charts are only a reference. from direct experience, load tables also are just a very rough starting point, expecially for major loads, where small changes can have large consequences.

 

i reload using SP2, which is a very good powder for major loads. 

i have suffered for a very long time from occasional malfunctions i could not solve. occasionally the gun would not cycle properly, or jam with a funny FTF

 

took me two years and thousands of rounds to figure out the problem

problem was that i was using a quite large OAL, due to the continue brainwashing of colleague shooters that you NEED long OAL in ma

so i was loading at the limit of 9x19 specs, 29.7mm, and beyond. 

at that OAL and with the material i use (FMJ 124 grs bullets, mixed brass) i was right at the verge of the case volume where pressures drop below the point where combustion becomes very poor and erratic

so every now and then a combination of the tolerances of brass, OAL and powder amount caused the ammo to burn so poorly that the gun would not cycle properly and jam

but i didnt know that yet, so, trying to cure the FTF problem, i increased OAL by a tiny amount, perhaps 0.1mm. due to lack of time i diodnt chrono the ammo

at the following match, the EEO, i was picked for chrono test. my ammo chronoed so bad that i was demoted to minor
some rounds, also due to cold weather, chronoed less than 1000fpm! 

 

so i went back to the drawing board, reduced powder amount by 0.1 grs, and shortened OAL to 29.4mm

all the realiability problems went away. chrono results became constant and consistently above 165PF
shorting the OAL i reduced the case volume enough so pressures were high enough to guarantee proper burning under any condition

erratic PF disappeared. cycle problem disappeared. reliability problems disappered. havent had a bad ammo or a jam since then.and gun stays much cleaner, i can shoot 2000+ rds without having to clean the gun, 

 

the choice of powders for 9mm major is not very large. id recommend sticking to proven recipes and materials. the comp will work. and if it doesnt, perhaps is not the comp...