Rifle Troubles

[bobgengeskahn]

I will post pics later, but this is the gist of how my mini has been moded:

14" factory barrel (cut from standard length) with a perm. attached FAL brake for an OAL of about 16.5"-17"
Ramline synthetic stock
Ultimack rail with an Burris 3-9x30 on low profile rings as a scout optic

There are 2 main problems:
1. The receiver is having problems cycling with the super low chamber pressures. So I am debating cutting down the factory spring? Has anyone done this? OR I read a thread a while ago about creating a gas piston for the Mini. I thought of an easy way to do it, and have been contemplating it to a. reduce the weight of the slide and b. cut down the chamber pressure needed to cycle the action.

The other problem is that the optic I have mounted was waaaaaaaaay off when I was at the range. I shot at the corners at 50yrds. to try to get on paper and couldn't do it. So I shot the berm out at 210yrds. (the lanes to my left were all clear) to see my POI on the berm, and it was a good 6-8' high and 8-10' right at 210. So does anyone have recommendations on how to shim the scope both up AND right? The only way I have found is to shim to adjust vertical, not windage. Or could this be a problem with my new brake?

Any help will be greatly appreciated, and I will try to post pics later just because it is also a really cool looking set up :D

[Walkenbear]

Hi bobgengeskahn,
Just a couple of ?'s about #1.
How did your rifle cycle before you cut the barrel? Any problems?
Are you using factory ammo or handloads? What kind of ammo or powder?
Are you running the stock factory gas bushing?

I wouldn't mess with the spring just yet, it's kind of important for timing of the cycling motion.

I think it's a gas issue, :unsure: OOPS! pardon me!
Should be able to figure it out.

[bobgengeskahn]

Hi bobgengeskahn,
Just a couple of ?'s about #1.
How did your rifle cycle before you cut the barrel? Any problems?
Are you using factory ammo or handloads? What kind of ammo or powder?
Are you running the stock factory gas bushing?

I wouldn't mess with the spring just yet, it's kind of important for timing of the cycling motion.

I think it's a gas issue, :unsure: OOPS! pardon me!
Should be able to figure it out.

Before it cycled fine and threw brass just as far as any mini with 55gr or 65gr. Today I was just using factory loads. Remington 55gr fmj, surplus 5.56 55gr FMJ and a couple rounds of left over wolf 55gr that i wanted to get rid of. my feeling is that it would cycle fine with 65 since it would usually either stove-pipe or re-set the spent shell.
edit: however, i wouldn't want to be stuck with just using 65gr since i prefer 55gr in my AR most of the time :-p

At the moment I have the factory gas block but its pretty ratty (i got it used originally) so i have been debating getting a new one or getting the ASI block. the only thing preventing me from getting the asi block is that i have heard that you can change your POI dependent on where the setting is. so although i would like to be able to set it to single shot when target shooting or whatnot, I wouldn't want it to change my POI if I didnt reset it to the same point when i wanted to shoot semi.

[Walkenbear]

I have never had an adjustable, but have also heard that the POI will change with adjustment. I think a good first step would be to get or make a set of gas bushings and try them out. We had a thread about gas bushings going on a little while back, I'll try to find it and post a link tomorrow, It's sleepy time now, gotta go get my PJ's on.-_-

[Archey22]

try cleaning out the gas bushing. It's possible that it is full of crud. When you take the gas block apart be sure to re-gap it and torque the screws evenly.

Your scope rings might need to be laped for the scope.

[tri70]

I agree with giving a gas block a good cleaning. What type of mount are you using? Do you have a bore sighter?

[steve4102]

The first thing I would do is take it apart and give the barrel, gas port(barrel), gas pipe and gas bushing a good cleaning. I would also check to make sure that the guide rod is installed properly and remove any shock buffers. If that doesn't help, I would take a drill bit and open up the gas bushing a little bit.

[Marlin 45 carbine]

you may have to file the contact surface of the locking tabs of your rings to bring the scope into alignement with the bore for windage. I had to do that. I filed the front one only - go easy and use a triangular file. file the stationary lug not the moveing lug.
the vertical I don't know - mine was dead on with the scope centered.

[bobgengeskahn]

Thanks for all the replies! I finally got a chance to break her down tonight and clean out the gas block. It was pretty clean as I make it a point to clean it every time I shoot, so I don't think that was really an issue :-/ sad because it would have been an easy fix. Archey: what do you mean about re-gaping the gas block? I have heard a lot of crazy things you can do to your gas block, I usually just end up putting it back on there.

For the scope I have low profile Ironsighters I got off of cheaperthandirt. they are really sturdy rings which is why I chose them. I have never mounted my own optic before so I've never used a boresighter. I don't understand what the difference between the $40 one and the $400 one is, does that really make that much of a difference?

[bobgengeskahn]

For those interested, I posted pics in this thread http://www.perfectunion.com/vb/showthread.php?p=482352#post482352

[Archey22]

by re-gaping the gas block, I ment to be sure both sides of the gas block are gaped evenly. Also be sure to properly torque the four screws in the gas block evenly. It's in the tips and tricks section.

[tri70]

Maybe turn the front scope ring around and see if it would correct the poi. If you can get ahold of a bore siter I think that would help too. Also try dragging a Q-tip across the crown to see if there is a bur giving you fits.

[Marlin 45 carbine]

you may have to file the contact surface of the locking tabs of your rings to bring the scope into alignement with the bore for windage. I had to do that. I filed the front one only - go easy and use a triangular file. file the stationary lug not the moveing lug.
the vertical I don't know - mine was dead on with the scope centered.


this applied to my Ruger rings, for my M30. mounting a scope they held it off-center so I filed one of them to bring the scope into alignment.

[JasonAC556]

OR I read a thread a while ago about creating a gas piston for the Mini. I thought of an easy way to do it, and have been contemplating it to a. reduce the weight of the slide and b. cut down the chamber pressure needed to cycle the action.



A whole lot easier and more cost effective way would be to just install a gas port bushing with a larger hole. The AC556K with the 13" barrel uses a .070 gas port bushing. The standard gas port bushing for a standard Mini is .050.

I would open up your bushing before I would try anything else.