Doing some trigger work on my mosin repro sniper.

[derr12]

So i stripped the bottom elevation screw on my mosin repro sniper by accedent. Got mad, took my toys home. later i realized i could simply swap the top for bottom and ill have good threads in the areas that matter again.
Next time out i got it dialed in and printing about a 3 inch group @ 100 with a few bad shots. What I found was that I was prone to pulling my shots right because the trigger pull is so damn heavy. It's pretty crisp by mosin standards, just too damn heavy. (Iprobably dont have the most advanced trigger technique in the world either)

so I started tinkering with shims under the sear, and while this shortened the long pull, it created too much slack for my liking and didn't do too much for the pull weight.
Started looking around and I found this aftermarket sear kit from smith sights; http://www.smith-sights.com/two-stage-triggers.php
Figured I might as well shim and cork the thing too and ordered his kit for that, came out to 87USD after shipping for both.

I know what yall are gonna say, yes i could bend or grind my current spring for almost nothing, but i don't have a spare. This one thatI ordered comes polished mirror smooth and blued so that saves me a couple hours of dicking around.
While i wait for it to arrive im going to polish the area that the sear rubs on on the bolt... naw fudge it, this modified bent handle bolt was so roughly thrown together that i might as well do a proper polish on the whole damn thing. It's just a repro, i can polish the bolt to make it look nice.

I figure the trigger pull was somewhere in the neighborhood of 8 or 9 pounds. Once it's all done ill let you guys know the results in case you were thinking of doing the same thing. Results will be from the same ammo, same location, same hillbilly bench rest.

 

[derr12]

the before photo. Right side is before removing a shim from my mount and very minor windage adjustment. This one doesn't show the flyers pre-adjustment, it's off camera.

 

[MuthaFunk]

Looking forward to the follow up. Keep us posted!

 

[derr12]

well i got bored of polishing the mosin bolt so i went out with my rescue pet sks. its got pitting in all the rifleing, the last couple inches of the bore is a nightmare. there is chipped crome about 3/8ths big at the crown. even still look at this group on a cheap chinese 9x scope @ 100m w/ surplus ammo

The one thing that saves me is the trigger on this garbage can of a rifle is phenomenal.

and a picture of my "bench"

 

[Josh Smith]

Tag -- would like to see this.

 

[derr12]

bolt is done. it's baby approved!

 

[derr12]

There was some deep pitting on the big part of the cocking piece, I wasn't willing to sand that deep so they remain. I'm most proud of the finish around the bolt handle. It was a mess and it's near perfect now. I normally wouldn't advocate a shiney bolt on a "sniper" but if its too obnoxious I can always hit it with 1000 grit for a matte finish that doesn't suck.

 

[derr12]

Received my trigger kit and shims. Here is what the product looks like side by side with the old sear;

The trigger itself uses roller pins to eliminate the frictional forces against the sear as much as possible.

The trigger pull weight is about half of what the old one was. The pull is smooth and consistent, and the break is crisp and predictable. I think i'm going to install a washer or bend the sear a little to shorten the second stage a bit, but not till after i get it shooting to see how it does like it is now.

Will update tonight or tomorrow with a range report.

 

[MuthaFunk]

Great thread!!! Keep us posted!

 

[derr12]

The maker of this sear advised against shimming and instead recommended i bend it to get the desired effect. says it may change the geometry of the sear engagement to a point of not-so-safe.

 

[derr12]

This first picture is me on my hillbilly bench rest, fired about 10 rounds to get it sighted in first. I found that the sand was too soft today, i was wobbling back and forth pretty bad i might need to upgrade my table. Knew i had two flyers before i checked my target.

giving up on the table I went prone after a few more fun shots. barrel was starting to get pretty warm, but not too bad.

So id say there is a marked improvement overall. I think a little practice on a proper bench i could make golfball sized groups on this surplus ammo.

Does anyone have any suggestions for taming that vertical stringing? Im 60% sure its the rifle and not me... it could also just be my prone stance. I shimmed the action and corked under the front barrel band.

 

[MuthaFunk]

I bought an accurizing kit off amazon and it worked very well. It came with quite a few aluminum shins and all the cork you'll need. I simply followed the instructions and got great results. It's just a run in the mill Mosin with a $22 scope mount and a $40 AIM 2-7X32 scope.

And my first attempt at 200M with it!

I did some trigger work to it as well but I think the accurising kit made a huge improvement.

Here's my portable bench set up. You can buy these portable pick nick tables from Canadian Tire for $50 made with pine or plastic like mine for $30 at Factory Direct.

I use my cooler to transport ice cold 0.5% Beer and serve as my elevated rest for the rifle. It works well for me.

 

[Josh Smith]

Hello MuthaFunk,

You do realize that the shim kit on Amazon is a direct rip-off of mine, right? It also runs about twice as much. The same person ordered and copied a shim kit by Brian Rau, who does Russian-style kits.

As well, they cheaply copied my front sight (and theirs is not fiber-optic, as they claim). They also stole Brass Stacker's removable pull ring for the Mosin's cocking piece.

Regards,

Josh

 

[Josh Smith]

This first picture is me on my hillbilly bench rest, fired about 10 rounds to get it sighted in first. I found that the sand was too soft today, i was wobbling back and forth pretty bad i might need to upgrade my table. Knew i had two flyers before i checked my target.

giving up on the table I went prone after a few more fun shots. barrel was starting to get pretty warm, but not too bad.

So id say there is a marked improvement overall. I think a little practice on a proper bench i could make golfball sized groups on this surplus ammo.

Does anyone have any suggestions for taming that vertical stringing? Im 60% sure its the rifle and not me... it could also just be my prone stance. I shimmed the action and corked under the front barrel band.

Hello,

Tighten the rear screw down in 1/8 turn increments. This will give you less load on the barrel. You can also move the cork forward or aft.

My Mosin uses 35in-lbs front and back, but it's also pillar bedded (mostly to protect the stock because I take it apart so often.) I'd play with the 15in-lb to 25in-lb range on yours.

Edit: A couple other options would be to leave the handguard off to let the barrel cool faster (and give it time to cool). You could also cut the pressure pad (cork) in half and install half on the upper handguard directly opposite that of the lower. I've been thinking about modifying the shim kit to work this way and have been running a prototype like this for a while now. The biggest problem is that some folks don't have the clearance to run both top and bottom. If you can, do!

Regards,

Josh

 

[derr12]

I def don't have clearance to run both top and bottom. Was quite a fight to get my front barrel band back on with just the bottom. Backing off the front screw a wee bit will take some of the barrel load off too I assume? im going to try moving the cork to the front and see, pretty sure thats where the finns stuck it back in the day isnt it?

Smith sights shim and trigger kits are the real deal. Gun shoots better much better than the putz behind it now.

 

[Josh Smith]

I def don't have clearance to run both top and bottom. Was quite a fight to get my front barrel band back on with just the bottom. Backing off the front screw a wee bit will take some of the barrel load off too I assume? im going to try moving the cork to the front and see, pretty sure thats where the finns stuck it back in the day isnt it?

Hello,

Backing off the front screw will have the same effect, yes Sir.

The Finns would shim or collar barrels wherever they worked. Moving the shim up front and moving it back to find the accuracy node will work best in your case, I think.

Regards,

Josh

 

[BucketOS]

I get the vertical strings as the barrel heats up or at least that's what I blame it on! I have shimmed and 'floated' several Mosin rifles including a M44 and get the same result. My SVT 40 does the same and I haven't done much to that rifle.

 

[BucketOS]

Hello MuthaFunk,

You do realize that the shim kit on Amazon is a direct rip-off of mine, right? It also runs about twice as much. The same person ordered and copied a shim kit by Brian Rau, who does Russian-style kits.

As well, they cheaply copied my front sight (and theirs is not fiber-optic, as they claim). They also stole Brass Stacker's removable pull ring for the Mosin's cocking piece.

Regards,

Josh

Josh, are your shims brass? I've had a lot of luck with brass in various gun projects. I'm curious about your thoughts on this. When I was really young I watched a home theater amp engineer lace one of his creations with brass to 'improve harmonics and increase energy efficiency'. While I'm certainly not a scientist and not sure if he was right but I guess that made an impression on me.

 

[derr12]

My svt-40 has a foot high vertical string, couldn't possibly be my eyes, no sir. To be fair it isn't saddle in its original stock I likely have some fitment issues. Dead on center tho. considerably better iron sights than the mosins fo sho.


I will tinker with the screws and cork and see where it takes me. After i find a sweet spot ill try some decent ammo instead of this Bulgarian light ball.

 

[Josh Smith]

Josh, are your shims brass? I've had a lot of luck with brass in various gun projects. I'm curious about your thoughts on this. When I was really young I watched a home theater amp engineer lace one of his creations with brass to 'improve harmonics and increase energy efficiency'. While I'm certainly not a scientist and not sure if he was right but I guess that made an impression on me.

Hello,

My dad's a retired electrical engineer, and I was raised in that environment.

I believe brass is superior for electrical applications. I'd go so far as to say it's likely second-best to gold. I don't recall having any aluminum in my home theater, though there's some tin solder in there. I should make it clear that the "home theater" I have is not much at all. It's the amplifier/tuner, two speakers with 12" woofer, mid, and horn tweeters, a turntable, a CRT flat screen (because the Nintendo Zapper doesn't work on LED and LCD TVs), a combo VCR/DVD, and a Micca media player. It would be a midrange '90s system

The reason I choose it for shimming applications with firearms is only because it's easier to work with than steel, and does not have the galvanic corrosion associated with combined aluminum and steel. It's pretty neutral and non-reactive and I prefer it for this reason.

Regards,

Josh