[cajungeo]

Welcome to the forum bbm. There is a lot of info in the mini about tuning your mini. The first thing is to determini what ammo shoots best in your mini. Some may shoot groops 1/2 as tight with one ammo than with another. Get a box or 2 of several different brands, and weights. Head to the range with benchrest, or bipods, or plain old sand bag works well. That being said:
(1) Select ammo
(2) Install muzzle brake ( I have a BlackWarrior $19.95) Will typically cut your average groups in half!
(3) Bed stock. Will tighten average groups, and get rid of flyers!
(4) Trigger Job (Done)
(5) Scope it (Done)

That should get you down to 2" groups or less at 100 yds. Mine shoots 1 1/2" groups with Winchester 45 gr. varmint (best group .92"). 1.15" with reloads (best group .85")

Note: I didn't cut my barrel, some have, and had similar results.

Use the search button above right, and enter key words for more details, all related posts will come up.

 

[wahturi]

wow. considering your results, 3.5 to 2.3 inch average groups, bedding is definetly the first thing to do on this rifle. and the fact that it eliminated the flyers! my mini has around 400 rounds through it. does bedding only benifit older guns that have gotten loose, or can i see an improvement after bedding my new mini? also, how do muzzle breaks help so well? can anyone explain to a newbie?

 

[voruzon]

Cajungeo forgot to mention Mike's reduced gas bushing! It's $25, reduces recoil, muzzle flip, wear and tear and most likely improves accuracy because the way gas is vented, it puts bending pressure on the barrel at the gas block.
Less gas is vented, less pressure hit on the barrel.

I'd put bushing as (1) - before the bedding, since you can do it in half an hour without any mess.

I'd also select ammo as the last step - your Mini will shoot quite differently with the new bushing - whatever one of Mike's three you are going to end up using, muzzle brake/barel end weight and bedding. Quite possibly it's ammo tastes would change.

V.

 

[mtnwatcher]

Wahturi,

if i read this post right, Z-man was bedding a new mini. so i'd advise you to bed yours. look for an article by Ed Harris on tuning the mini on this forum. i think i did a search on bedding, or slide channel when i found it. he explains alot about bedding the mini.

i've bedded mine twice. the first time i didn't bed the stock reinforcements to the stock and the bedding stopped working. this time i did it right i think.

first i took a dremmel and ruffed and pitted the choates stock i wanted to bed.

second i bedded the slide channel and where the slide cap assembly sits. that took alot of glass. let it sit overnight.

third i bedded the stock reinforcements. let it sit overnight.

fourth i bedded the trigger group, includding around the mag well, and the reciever. don't close the trigger group when you do this. leave it about 1-.5 inch open. i used tape to secure it. let it sit for four days. i put 50 rnds of wolf ammo to settle the bedding. then i shot my handloads to check for accuracy.

2.5 groups form prone supported @ 100m.

 

[mtnwatcher]

doh!

i just found it out on the web. the article, i mean. it was actually written by John Masen.

 

[mtnwatcher]

i guess it's gonn be one of those days.

the article was written by James Mason.

now i'm going back to bed.

 

[wahturi]

thanks, i will be reading that shortly.

 

[cajungeo]

If I may add a few comments:

The gas bushing dosen't seem to change accuracy by a significent amount, except by reducing felt recoil way down, so one is better able to keep sights/crosshairs on target during rapid fire. The bushing reduces recoil, by reducing the gas operating the slide rod assy, and bolt. Instead of a harsh rearward movement it is an easier movement. The noticable reduction in recoil is from a lesser rearward force of the slide rod/bolt assy, and not the cartridge explosion. The velocity of the bullet is only increased aprox 4 fps. so it will not likely change your favorite ammo, as the barrel harmonics are not changed as they may be by adding a muzzle brake. After adding my muzzle brake, and firelaping my barrel, my worst ammo Winchester 45 grn varmint, became equal with my best Federal Premium.

Bedding will improve any rifle whether it be an old rifle, or new. It only serves to fill the gap between the receiver recoil lugs, and stock, so the force of the cartridge explosion does not allow the receiver/muzzle to move inside the stock under fire. On my mini The .030" gap allowed the muzzle to move up to 3" (those lousy flyers). Bedding my mini tightened groupage an average of 3/4", and no more flyers. It works for me.

 

[mtnwatcher]

Z-man,

by way of clarification, the groups that you posted in this thread, were those done with or without the muzzlebrake and or factory front sight?

 

[Z-Man]

The final groups were shot after shortening barel, without a muzzle brake, and with a Pentax scope (at 24x) from a machine rest.

 

[mtnwatcher]

do you think that putting on a muzzle brake or flash hider after shortening the barrel would decrease accuracy? or would the barrel be stiff enough not to change the harmonics?

 

[Z-Man]

mtnwatcher,

Since I have not yet had a chance to test my shortened Mini with a muzzle brake, I do not have a direct or conclusive answer to your question with what I consider to be verifiable, specific, or measured results.

However, I can tell you (from a pure physics standpoint) virtually ANYTHING/EVERYTHING that you might do to alter or change a barrel (mass, temperature, stiffness, length, etc....) WIIL ultimately change its "harmonics." Even a 1 gram, 1" long-by-1" wide piece of scotch tape stuck to a barrel will change its harmonics (the resonance frequency will drop). And even though you might not be able to measure the change with a ruler on your targets, you can take it to the bank that the harmonics on in the barrel have definitely changed.

I do plan on soldering on a muzzle brake in the near future...and of course, I wil be testing it thoroughly and reporting the results here for all to see.

 

[cajungeo]

z-man, did you ever firelap your barrel? It tightened my average 5 shot groups at 100 yds. by 1/4". That may not sound like much to some, but a quarter here, and a quarter there, adds up.

 

[Z-Man]

cajun,

No I haven't done that yet, but I do remember reading your post many months back where you covered your good results with the lapping.

I did (still do) have a number of things I wanted to measure and get before-and-after readings on...and mic'ing the bore to check for runout was (still is) on the list.

And I hear you loud and clear on the 1/4" impovments....they really do add up.

 

[mtnwatcher]

some of my gun buddies told me that firelapping wears out the barrel faster and that a gun as old as mine doesn't need it nor would it be good for the barrel. i got a 183 series blue, and i got it used so i don't know really how many rounds it has fired.

whaddya think Cajungeo?

Z-man,

forgive my ignorance but what do you mean by ''mic'ing the bore to check for runout''? is that a way of determining if the barrel should be firelapped?

 

[cajungeo]

No it dosen't wear out the barrel, if done properly.

I agree with you, on an older rifle, with several thousand rounds thru it, it's probably already laped.

I bought my mini new last year. The bore was very rough. I could even feel it with my cleaning patches. Laping the bore smooths the machine marks, and polishes, by using progressively finer grit. I started with Mike Knifongs kit 220, 320, then 600 grit. After viewing mikes bedding video (he shows ya how to make lap bullets) I would probably make mine, but you have to buy the grits, and at least 30 lead bullets. Mike sent 60. Enough for 2 mini's or one real stubern one.

A smooth, polished bore does 3 good things for the rifle. It improves accuracy, increases time between cleaning (less fouling), which will keep your accuracy for longer strings of firing, and to a small degree reduces barrel heat.

The benchresters hand lap their expensive match barrels, by pouring molten lead down the bore to make a slug of lead, which is then imbedded with grit. I like firelaping cause it does a good job, and it is quick, and easy.

My personal view is, I would lap a fairly new mini, not an older one that's been fired several thousand rounds, as I doubt you would see any improvement. I also wouldn't lap a match barrel, as most manufactures, say it isn't necessary as they lap, and polish the bore. Just my 223 cents.

 

[Z-Man]

The term " mic'ing " is just a short way of referring to the process of running a special micrometer down the bore to check for variations in diameter.

 

[Mughi-14]

Z-Man,

It is entirely possible that I am a complete idiot here, but I'm a bit baffled by your cutting method. Removing 1/4" at a time sounds pretty precise (far more than my skills are capable of, I fear). Did you cut it down in a lathe or with a saw and then true up the facing with a piloted-facing cutter?

I thought that lathe work required tearing the barrel out of the receiver, which would make your efforts all the more impressive (as if they aren't already).

How did you do the shortening process? Thanks.

Mughi-14 (the "not too mechanically inclined")

BTW, did you get a brake put on it yet?

 

[Z-Man]

The cutting was done using an industrial precicion abrasive-wheel (diamond) cutting machine.

This particular machine (I believe it was made by Metal Cutting Corp.) has the capability to handle both irregular and tubular shaped material and utilizes multiple-clamp and carriage system to hold, align, and manuever the piece being worked on. Since the unit is designed to handle odd-ball and irregular-shaped objects it was not necessary to remove the barrel for each seperate cut.

Using this machine you can get cuts within .005" every time, so facing and crowning was a snap. I just used the "ol standby" Brownells hand cutter with pilot and the 11-degree recessed target bit for final work.

You certainly COULD take off the barrel and run it on a lathe, but the time vs. effort on a $63 Mini barrel would be way to high....(especially in hindsight, since I ended up making a total of 8 cuts and crowns along the way).

As for the brake, no I have not re-installed it yet.

Once I got to messing around with it, it became obvious that I would have to either enlarge the inside diamter of the brake or decrease the outside diameter of the barrel on the lathe. Since threading the barrel is out of the question on a 196 series, and since I don't know how the brake will affect accuracy on the shortened barrel, I don't really want to silver solder the thing on and then be stuck with it should it have a negative effect on accuracy.

 

[Mughi-14]

Now it's all coming together in my mind (it will soon be gone, mind you, but it's there now).

Thanks for the information. An 11-degree crown bit... excellent.

I appreciate it a lot. Hacksaws aren't my forte, but I might have access to similar cutting machinery through some mechanical-friends.

Mughi-14