[Shawn Watson]

Hi all,

I am a newbie (just bought a mini 30 yesterday). I have been searching on the board about popular modifications to these guns. I would like to improve the accuracy and reliability of my riffle. So far it looks like i will be buying a Muzzle Brake, Recoil Buffer, and a sythetic stock. All these modifications seem to improve accuracy.

Do you guys know of any drawback to doing any of this to my new riffle?

I have heard about people buying gas bushing. It seems the slow down the bolt and keep from slinging brass so far. Is this the only purpose of this modification?
Where do these bushings go? How hard are they to install? I have to say i am not very familiar with the internal workings of this riffle yet. I field stripped it last night to clean it but don't completely know all of its operations yet so please be simple
Is there any draw backs to installing these bushings?

I really appreciate the help.

Thanks
Shawn

 

[Satan2655]

The Bushing is a tiny cylinder which resides inside the gas block. The Main gas port is a hole which is tapped into the barrel at a 90 degree angle to the barrel (under the gas block), and allows some of the gases from the powder burn to leave the barrel (after the bullet passes by the hole). The orifice in the Bushing is smaller than this hole, and regulates the quantity and pressure of gas going through the port. The smaller the orifice in this Bushing, the less pressure and quantity of gas is let into the main gas port. When the gas travels through the main gas port and Bushing, it takes another 90 degree turn (toward the butt of the gun) and is let out of the gas piston. This burst of hot gases pushes the op-rod backward, which cycles the action.

Mike Knifong's gas port kit consists of 3 Bushings, all of which have smaller orifices than the factory Bushing. There is a Large, Medium and Small. If your gun is new, you will probably end up with the Large bushing, but try the Medium one first. They are not marked, but depending on your eye, it is pretty obvious which one is which. I use the Medium one since my gun cannot seem to completely cycle with the Small Bushing. Your results may vary depending on how strong your op-rod spring is.

The advantanges of the smaller orifice kit:
1) Shorter ejection path. Your brass ends up a reasonable distance from your gun, instead of 60 feet away.
2) If you reload - you will get less damaged brass because the op-rod doesn't come back as quickly to bat the round away.
3) Less wear and tear - smoother, slower cycling of your action results in better longevity of your gun.
4) Less felt recoil - your scope will last longer and you will be able to remain on-target better.

There really is no accurizing effect that I know of, but there might be.

The disadvantanges of the smaller orifice kit:
1) You may experience jams because the gun does not fully eject the shell, or does not push the op-rod rearward far enough to pick the next shell off the top of the clip.
2) The bolt may not lock back after the last round because it did not go far enough rearward to catch on the bolt lock.
3) No other disadvantage I know of.

Replacing the bushing is VERY simple. I do it in the field all the time when I am tinkering. You just need an allen wrench of the correct size. Take your gas block apart with the four screws. Loosen all of them before taking them out completely, or you may get them bound and end up stripping a screw.

The Bushing sits in a counter-sunk hole in the barrel where the port is, under the gas block where the piston sits. IT IS VERY EASY TO LOSE THIS LITTLE SUCKER. Swap the Bushing, and put the block back together. Make sure the Bushing is properly seated before tightening your screws! Put a little Locktite BLUE on the screws before re-assembly. Make all the screws barely snug before tightening, at the same time making sure the gap between the block halves is equal all around. DO NOT CRANK ON THESE SCREWS! They don't need to be Godzilla tight. I use the short end of the Allen wrench for leverage and use medium thumb-and-forefinger strength (17.284 ft-lbs). JK

Hope this helps.

 

[bushwack]

Satan---Not only a good explanation of Mikes gas bushing kit but also a fine discription of the way the gas system on our Minis operates. Should be required reading for first timers.

Well done
Bushwack

 

[cajungeo]

Very good satan, I will use your post as reference reguarding future questions on gas port bushings.

 

[Shawn Watson]

yes that was a great description. I figured there had to be a hole in the barrel somewhere that let gasses get to the big piston thing under the barrel. I took it apart last night to see if i could figure out what makes it tick. Figured it had to be a setup like that.

I might get a slightly smaller orifice but i still want it to be pretty fast.

Thanks
Shawn

 

[EdinKali]

Another alternative to the gas bushing is a stiffer recoil spring. My brass usually ends up less than 10-12ft. away now. You can get a stiffer recoil spring from gunsprings.com for about $12. If you have a ranch rifle, you don't really need a recoil buffer as the ranch rifle has one built in(regular mini's don't have that AFAIK). If you go with the heavier recoil spring this also lessens the need for a recoil buffer.

If you go with the gas block bushing, make sure you don't tighten the bolts to 17 ft lbs as that would strip out those tiny bolts. The correct torque is 17.2-17.3 inch lbs. Big difference.

 

[Satan2655]

LOL! I guess I just have really strong fingers! You are right, its inch-lbs. LOL

 

[cajungeo]

you don't really need a recoil buffer as the ranch rifle has one built in (regular mini's don't have that---)

Edin, Using proper Ruger names for parts to make shure we are understanding each other, the "Slide Assembly" in my Ranch mini under rearward movement (toward my shoulder) makes metal to metal contact with the "Buffer bushing". There is no rubber recoil buffer, as I understand your terms. True the stronger spring will restrain the rearward movement of the Slide Assembly thereby lessening the rearward impact (recoil), but the offside is it will increase the forward (toward the gas block) metal to metal contact with your gas block. Your scope will feel it. A stronger spring is kinda like using a bigger hammer. Another thing with using a stronger spring, if you do a search on firing pins, we had a couple 3 shooters with broken firing pins. We are not for certain why theirs broke several times, but a stronger spring would increase the inertia impact of the firing pin. The smaller gas port bushing will put another 4 or 5 fps behind your bullet rather than waisted in the gas block. Now I'm not saying a stronger spring is bad, I would rather have a stronger spring than out of the box set up, its just my opinion that a smaller gas port bushing would be a better overall solution to excessive recoil, which the stock mini has. With the muzzle brake, and smaller gas bushing the muzzle flip, and felt recoil is only a little greater than my 10/22.

Good point you brought up 17 (ft/lbs) =12x17 (in/lbs)
It was only a Typo error.

 

[cajungeo]

I might get a slightly smaller orifice but i still want it to be pretty fast.

Shawn installing a smaller gas port bushing, will slow the rearward movement of your bolt, by probably by as much as a milli-second. It won't slow your rate of fire ANY! Shoot your mini for a while as is, so you can get used to the kick. Then if you install the smaller gas port bushing, you WILL BE AMAZED PERIOD

BTW; To all you guys, and gals, I know I have been pushing Mike knifongs bushing kit since my first post. I will tell you this, I do not receive any favors, kickbacks, or commissions from Mike or anyone else. As a mater of fact till last week Mike didn't even know who I was. However I do get something from it, I get satisfaction when someone reports their results Then it makes me

 

[EdinKali]

Satan2655: I had an old friend from high school that stripped out a bunch of rocker arm bolts in his Mopar 340 when he attempted to torque them to 80 ft. lbs each. He missed the part that said inch lbs. Ever since that, I pay real close attemtion to the ft./in. lbs notations.

cajungeo: Yeah, you are right. Recoil bushing, not an actual rubber recoil buffer. I figured they updated the Ranch with that feature since they figured most Ranch buyers would be putting a scope on the rifle. If the Ranch rifles still benefit from the rubber/plastic recoil buffers I may have to get/make one. I think I have some scrap urethane around here somewhere. I may also just try a couple dabs of automotive high temp silicone at each end and see how that goes. I'm tempted to make my own gas bushings by machining some drill rod. Shouldn't be too hard to make.

I'm curious about those broken firing pins you were talking about. I wonder if they were using mil-surplus ammo with the hard primers. I hear Ruger doesn't recommend firing the hard primer stuff due to broken/bent firing pin issues.

 

[cajungeo]

Hey Edin, You can try to make your own gas bushings. The std Ruger is about this big (o). The largest of Mike's bushings is about (.) this big. The other 2 sizes are smaller. He made them from 4016 satinless steel. Have no idea how he drills holes that small thru such a tough hard metal.

As far as broken firing pins, I believe some shooters were having ocasional misfires or very lite pin strikes on the berdian primed ammo so they installed the heaver springs. I believe (my opinion only) the strikes ocassionally hit the partition between the two flash holes, puting a diagonal force on impact, on the firing pin amplified by stronger slide assy springs, resulting in metal fatigue over time. The subsequent, and frequent breaks, a bad batch of pins?

 

[EdinKali]

I'm using regular boxer primed handloads now so I'll let everyone know if I break a firing pin. At this point the heavier spring is working well enough that I don't feel the need for the gas bushing. My brass was all within 12 feet when I went shooting yesterday and the recoil is the same as my buddy's ar-15. I'll post the results of my range trip in the accurizing section.

 

[DKRichards]

EdinKali, how do your case mouths look? I would like to start reloading for my ranch model Mini 14, but the case mouths look really mangled. I don't know what's causing it, but have heard a smaller bushing might help.

 

[cajungeo]

DK, look on the outside of your slide rod assy, just infront of the handle, see the brass marks? The rounds come out so hard they hit or are hit, by the slide rod at this point, slaping em across the mouth. The smaller gas bushing reduces this to just a love tap, no bent neck mouths.

 

[EdinKali]

DK, case mouths look fine. Occasionally I'll get one with a small ding in it probably from hitting the cement or whoever is sitting to the right of me. Nothing a quick run through the resizing die can't take care of.

 

[DKRichards]

"The rounds come out so hard they hit or are hit, by the slide rod at this point, slaping em across the mouth."

Thanks for that info. Can I order a smaller bushing and install it myself? I am reasonably mechanically inclined.

 

[cajungeo]

You bet DK, You can contact Mike knifong @ NW Shooter Support, at E-mail Address(es):
[email protected] The bushing kit has 3 diferent size bushings for $25, for another $25 he will throw in a 3 1/2 # trigger job (combo deal). He sends complete instructions with the 3 bushing kit. You can also do a search using keyword "bushing" and get tons of posts on this subject. It is easy to install.

 

[Satan2655]

...or just read above, I tell you how to install it.

 

[DKRichards]

Thanks, guys. I'll keep his email for when I'm ready to start reloading for the Mini. RIght now I'm busy working up loads for my Savage bolt action.

I'm guessing for the trigger job I'd send him the trigger mechanism? I've not taken my Mini down that far yet, but I suppose that's not too complicated to do? I've only had about 300 rounds through the Mini. I think I'vee only cleaned it once!

I know, I'm a baaaaaaaaaaad boy!

 

[gaar]

Will the bushings included in the kit work on the Mini30 also?
Or do I have to order seperate kits for the 14 & 30?