How to reduce recoil?

[ExtremeShot]

I need some advice. I'm trying to dial in my first Open gun and I'm having problems with recoil and high pressure. At 172 power factor I wouldn't think I would be getting high pressure signs, but I'm getting flattened primers and primer flow. The recoil is no where near flat.

My setup is listed below. Do you guys have any suggestions on what might be the problem or what I might focus on?

THanks,

Darren

38 Super Schuemann barrel

Frame/slide/barrel fit was done by Virgil Trip.

Slide has been lighten internally and externally.

8 lb recoil spring

EGW 7 port comp

Load (power factor=approx. 172):

Zero 124 fmj

9.1 gn HS-6

OAL=1.222"

Small Rifle Primers

crimp=.382"

[yoshidaex]

thats a nice looking gun

as for your pressure issues, i don't have experience with 38s loads but i do know my major 9mm loads are up there when it comes to pressure. I'm running 9.1 grains of hs6 at an oal of 1.16 with a 115 grain HP bullet for a PF of 175. I use nothing but winchester primers along with an extra long firing pin from dawson. the two items i listed won't get rid of the pressure issues but should help with the flattened/sheared primer issues.

Edited December 28, 2007 by yoshidaex

[rwmagnus]

[edit:That lighter bullet is most likely the issue. It's going to be snappier than a heavier one.] Sorry you did say you were using a 124 I thought it was a 115gr.

I shot a 38super against my 9mm Major last week and they we almost identical. Both pretty soft and flat.

38 super

124JHP

7.4gr Vit powder 350??

1.180"OAL

Winchestaer SP primer

vs my 9mm Major

124JHP Zero

8.3gr HS6

1.174OAL

Winchester SP primer

170PF

I don't have much experience with 38S but recoil is recoil. You need a solid grip, stance and correct springs. I use Wolff 9lb recoil. Your primers shouldn't be flowing. Are you over crimping the brass? Can you post a picture of a fired casing? That's a nice gun with plenty of porting it should be easy to set up. Try a regular pistol primer. Winchesters are harder than Federal and easier to come by.

Edited December 28, 2007 by rwmagnus

[JThompson]

Darren... got some images of the brass?

[G-ManBart]

9.1 of HS-6 is at the upper end that I've seen people use with that weight bullet, but not out of line with what some are using. 124/125s will have a little more muzzle flip than lighter bullets. You may want to try a 115 with a different powder. Recoil springs make a difference too. That 8lb spring might be letting slide come back harder and causing the muzzle to flip up. Do you have a 9 or 10lb to try? Anything heavier probably won't run, but my 38SC shorty with a lightened slide runs fine with a 10lb spring and 172pf loads without a lot of muzzle flip. Pictures of the primers are a good idea as JT mentioned. R,

[ExtremeShot]

Thanks for the comments guys. I guess maybe I have two separate issues here and they are not necessarily connected: 1) high pressure, and 2) too much recoil.

Regarding the recoil problem: I'll play around with the recoil springs and see if that helps. I may also try playing around with different powders to see if I can get the comp to work more. However, I don't like the idea of using a powder like Vitavouri that is expensive and hard to get.

Someone asked about my crimp, it is current at 0.382" diameter. It may be a couple thou tighter than spec but appears to not be too much. ...You can run your finger over it and feel the sharp edge.

Regarding bullet weight, I would think a lighter 115 gn bullet would be even snappier than the 124? ...I'd hate to change because I have about 7000 of these on my shelf.

I'm also going to rechrono my 9.1gr HS-6 load to verify that it is still around 172 power factor. Maybe something got screwed up and I'm hotter than I think.

Did you guys notice I'm using small rifle primers? I was told this is what I need to use in a 38super Open gun so that's what I did. I assume the rifle primer is hotter and helps the powder to burn more evenly/completely?? Could going back to a small pistol primer decrease the pressure?

Below are a few of the primers from my shooting session yesterday.

THanks guys,

Darren

[.40AET]

Try out a 9 or10# spring. When I was dialing in my open gun I went from 11 down to 7. With major loads I started to get muzzle flip when the slide hit then end of its travel. FWIW, I use a 7# spring for my steel loads and a 9# for major. As stated, the 115g bullets shoot flatter. They need more gas to make major and work the comp better. They are a little harder hitting in the hand, but the dot says in the center of the glass more. (Not snappier, but harder and flatter) If you can find IMR-4756, its slower and makes more gas and will fit in a super case.

Good luck.

PS- Your primers look like sh!t. Especially the one on the bottom left (smeared flat is bad). Lots of flow back into the firing pin tunnel. You should check them again on the chrono. The brass is getting beat up too. Don't try SP primers, they will be worse!! I would back up and rethink everything that is going on in my load. Keep the info coming.

Edited because OP was posting photos

Edited December 28, 2007 by .40AET

[yoshidaex]

pick up a extended length firing pin if you don't have one already. that should get rid of your primer flow issues.

as for your primer i'm assuming winchester small rifle? you might be able to get away with winchester small pistol primer. YMMV

Edited December 28, 2007 by yoshidaex

[ExtremeShot]

pick up a extended length firing pin if you don't have one already. that should get rid of your primer flow issues.

How does a longer firing pin get rid of primer flow?

[rwmagnus]

Thanks for the comments guys. I guess maybe I have two separate issues here and they are not necessarily connected: 1) high pressure, and 2) too much recoil.

Regarding the recoil problem: I'll play around with the recoil springs and see if that helps. I may also try playing around with different powders to see if I can get the comp to work more. However, I don't like the idea of using a powder like Vitavouri that is expensive and hard to get.

Someone asked about my crimp, it is current at 0.382" diameter. It may be a couple thou tighter than spec but appears to not be too much. ...You can run your finger over it and feel the sharp edge.

Regarding bullet weight, I would think a lighter 115 gn bullet would be even snappier than the 124? ...I'd hate to change because I have about 7000 of these on my shelf.

I'm also going to rechrono my 9.1gr HS-6 load to verify that it is still around 172 power factor. Maybe something got screwed up and I'm hotter than I think.

Did you guys notice I'm using small rifle primers? I was told this is what I need to use in a 38super Open gun so that's what I did. I assume the rifle primer is hotter and helps the powder to burn more evenly/completely?? Could going back to a small pistol primer decrease the pressure?

Below are a few of the primers from my shooting session yesterday.

THanks guys,

Darren

Darren

Have patience. Youre on the right track. I'd suggest trying a 9 or 10lb Wolff spring first, next use a standard Winchester primer then try a lighter bullet. Now is the time to try different things. Once you find the right combo you won't want to change anything. And yes those primers are starting to show high pressure flowing signs!

IF you find the lighter bullet works for you I'll gladly buy the rest of your 124JHP Zeros.

[yoshidaex]

the extended length pin prevents the primer from flowing back into the firing pin channel. its not a fix all for pressure issues but you won't end up with a primer channel filled with primer material and subsequently light primer strikes.

[ExtremeShot]

Darren

Have patience. Youre on the right track. I'd suggest trying a 9 or 10lb Wolff spring first, next use a standard Winchester primer then try a lighter bullet. Now is the time to try different things. Once you find the right combo you won't want to change anything. And yes those primers are starting to show high pressure flowing signs!

IF you find the lighter bullet works for you I'll gladly buy the rest of your 124JHP Zeros.

Yep, you must have patience with these Open guns. This is the first Open gun I've messed with and it's the "messing" that's the fun part for me. It's fun to learn and understand the mechanics of everything. ....my next Open gun build (9mm major) is sitting on my bench in a million pieces. I've got the rest of winter to get it running.

I'll take your advice above and keep track of all the changes and results. If you guys can think of anything else, please let me know. I'm also taking advantage of the forum search feature.

Darren

[yoshidaex]

Load (power factor=approx. 172):

Zero 124 fmj

9.1 gn HS-6

OAL=1.222"

Small Rifle Primers

crimp=.382"

Hey Ralph,

sorry to burst your bubble but hes using the FMJ variety of bullets

[Bear23]

Try increasing your OAL to 1.250" This may help reduce the primer flow. 9.1 gr of HS-6 is fine. I run 9.5 in my SV shorty with no problems.

For more gas you could try the IMR type powders.

[Kingman]

check something with your loads. I am under 9 with 115's and making 173

[AZ38super]

I don't have my load data in front of me but 9.1 with 124's for 172 PF is way high from what I remember.

I used under that for 115's to get around 172 PF (if my brain remembers correctly) so I would recheck them on a chrono.

I used to use N350 but now use IMR 4756 and like it, performs like 350 at a much lower cost. It appears dirtier at first but has not gunked up for me, In a test I ran around 2K+ rounds without cleaning and no issues in gun function.

[mcattack]

You do Have 2 different issues going on. The primer flow is the one I would worry about. Get a long firing pin and that should stop that problem.

Muzzle rise and recoil are hard to seperate. With out barrel ports your gun is going to have more muzzle rise. May feel softer but more muzzle flip. My gun has barrel ports and when I shoot a gun with out barrel ports it feels like it is going to jump out of my hand. Choicing the right powder is what you are going to have to work on to get the feel you are looking for. In my expierience Accurate #7 is dirt but flat, 4756 is flat, Vit 3n38 or flat shooting powders. Vit 3n37, HS6 and 7 or softer feeling but more muzzle rise. IT is going to depend on what makes you happy. I like the powders that shoot flat but they do give more vibration to the hand. It is going to take buying a few different types of powder and working up the load that feels best to you. The 124 GR bullets are fine and majority of open shooters if you look at stats use 124's. I personally shoot 124's because I lost a lot of my accuracy with 115's. The 115's are flatter but I felt like I was giving up to many points and missing to many plates to stick with them. Part of the fun in Open is you always have something to try or play with and change.

[rwmagnus]

Load (power factor=approx. 172):

Zero 124 fmj

9.1 gn HS-6

OAL=1.222"

Small Rifle Primers

crimp=.382"

Hey Ralph,

sorry to burst your bubble but hes using the FMJ variety of bullets

Oh well bubbles wern't meant to last forever. I'll be using the FMJ variety in the near future I'm sure. Zero is out to get us (JHP users).

[ExtremeShot]

I went to the firing range and my 9.1 gn HS-6 load chroned at 183/184 power factor, NOT 172. So that explains some of the recoil.

I also switched the firing pin to an extended pin and the primer flow problem went away (see the picture below). ...I would have never guessed that a longer pin would prevent primer flow.

I also chrono'ed two loads (ten rounds each) that were the same except one had small rifle primers and one had small pistol primers. I saw no difference. They both chrono'ed 183/184 power factor.

I also tested a 15 lb spring and a 11 lb spring. Less recoil was noticed when going from the 8 lb to the 11 and even the 15. I got a few failure-to-go-into-battery's with the 11 lb.

I plan to drop the powder down to give me around 170 power factor then go back out and test the different springs.

Thanks for the extended firing pin tip yosh!

Darren

Edited December 29, 2007 by ExtremeShot

[eric nielsen]

for primer flow:

with a standard FP, you had a LOT of flow for hs-6 and a 124. you should check headspace [the amount of barrel hood that goes past a loaded round in the chamber] and also check freebore [the distance a bullet moves before hitting the rifling - check with some xtra-long loaded rounds or dummy rounds]. you want both of these to be more than zero. the long FP is masking but not eliminating the problem.

you also want a hammer strut that leaves the hammer against the FP stop & won't let it back out. also a std or light FP spring. these are the opposite of what you want on a carry gun.

-----

for recoil:

you have a pretty nice setup, didn't mention your mainspring weight. if you run a real light hammer spring [17 or less] with a light slide spring [9 or less] you're probably slamming the slide at real travel. i use a 10.5oz slide, a 9lb slide spring & a 18lb hammer spring, HS6 behind a 115 Zero jhp.

some people see more pressure issues with one brand [MG] vs another [Hornady or Zero] or one diameter vs another. or especially after tumbling loaded rounds

some of us see HS6 as very friendly to using a 115 - as in, just about the same felt recoil with a lot less flip. most other powders don't do this. for me it was true in 9major and Super.

one thing that consistently cuts felt recoil is sideports - if you try it, make sure you drill in the right place, not too close to the top of the comp or it will crack.

Edited December 29, 2007 by eric nielsen

[yoshidaex]

I went to the firing range and my 9.1 gn HS-6 load chroned at 183/184 power factor, NOT 172. So that explains some of the recoil.

I'm thinking that 180+ pf was the culprit behind the sheared primers.

[jostein jensen]

And some of the recoil as well!

It takes a bit of ooomph to give 13-14 higher PF than needed

[Alan550]

That OAL looks a bit short as well. As Bear said, a 1.250" will lower pressures, and should run fine. The 1911 platform was designed around that OAL originally.

Alan~^~

[ExtremeShot]

That OAL looks a bit short as well. As Bear said, a 1.250" will lower pressures, and should run fine. The 1911 platform was designed around that OAL originally.

Alan~^~

Yep, I plan to increase the OAL as well. Thx!

[vernbo]

ANYONE else curious as to what is causing the large dent at the edge of the cases?