I have a Stainless  184 series  mini that I bought brand new in 1986.  I have easily  put 3-4K  rounds through it over the years.  I decided to take apart the gas block   and give it a good cleaning,  since it was apart I started to look into the smaller gas block inserts  that  are supposed to help accuracy ect.    most people online are having good  luck with the .040-.050"  range in bushing sizes.   Since the factory size is .085"  the reduction is supposed to make a difference.    I measure my factory bushing and  it is .085".  However , when I measure the gas port hole that is in the barrel its at .050".....

Ican see how going from .085"  to .050"  can make a difference but  .050" to maybe .040"  ??

what am I missing?

www.mini14gasblock.com
You can get adjustable gas block for Mini 14 without or with Stabilizing Bar (Strut)

Gas Reduction Kit Includes .035", .040", .045", and .050".

The Mini 14 is over gassed by design so that it will run with pretty much anything.

One of the frequent complaints from Mini-14 owners is that they'll throw brass 20-30 ft with some loads.  However, what some Mini-14 owners don't know is that the early Mini-14 (like your 184 series Mini-14) used a plunger ejector, while the later Ranch Rifles and Mini 14s have the ejector incorporated into the bolt stop.  It's the later Mini 14s that will throw brass into the next county.   You won't see much difference in ejection if you install a smaller gas bushing.

Most Mini-14s will run with most loads with an .045" bushing, so it's a pretty safe bet, while some will start to short stroke with some loads with a .040" bushing.  The differences include the specific load being used, as well as things like wear on the gas pipe and lubrication of the slide.

The other common addition to an older Mini-14 is a shock buffer - either a 1911 buffer, or one made for a Mini-14.  It'll chew up and spit out the 1911 bushing in a couple hundred rounds while the larger Mini-14 bushing will last a couple thousand.

Some shooters think the shock buffer gives it a smoother feel when shooting it, and some shooters feel the combination of a smaller gas port bushing and a shock buffer helps improve accuracy, although the greatest improvement for a thin barrel Mini-14 is an Accu Strut and a Choate flash hider. Both my 184 series Mini 14 and my 187 series Ranch Rifle will turn in 1.5 MOA 5 shot groups.

Thanks for he reply.....   I did not know that the newer Minis  changed there ejector styles.

I see on your Minis  you are using he Choate  hand guards,  is this for the cosmetic  "M14" look?

Does it actually cool better than the factory black plastic one and improve accuracy as some claim?

I actually had a wood handguard on the walnut stocked Mini 14 for awhile, but went to the Choate since it wood handguard does trap heat.

However, I'm not sure that the Choate is really any more effective than Ruger's plastic handguard - I just don't like the Ruger hand guard as it tend to rub on the operating rod/slide.

I've found that both my Ruger barrels are stable when they get warm with no tendency for the point of impact to start walking, and the overall effect on accuracy with a hot barrel is minimal.  At a steady rate of about 5 rounds per minute, my rifles will put the first 5 shots from a 20 round magazine in a 1.5 MOA group, while the last 5 will go into a 2 MOA group.