Ruger Ranch 7.62x39

[Mr Peabody]

How many of you who own this rifle have slugged the bore? And what did it measure?

[Loudenboomer]

I have a mini 30. Bores are .308. I haven't shot cast in mine but I can tell you that they are throated long enough that .310 .311 eastern Ammo will chamber fine. Some have stated only .308 bullets should be used. Firing .308-.311 has not been an issue in my rifle. Extra hard primers on the eastern ammo has caused reliability issues. I installed a wolf extra power hammer spring and it helped ignition problems considerably.

[atfsux]

BEWARE!!!!

Not all Ruger Ranch Rifles in 7.62x39 have the same bores. Early production runs used a .308 bore because, at that time, the Ruger cost more than an inexpensive Chinese AK. The conventional wisdom at the time was that Chinese ammo was crap and the only way to get better than 5 MOA with the cartridge was to handload your own. I think among domestic ammo makers, only Winchester even offered the caliber back in 86'. Cases were available from Norma and Lapua, and there were plenty of .308 bullets in the appropriate weight range available domestically. So as Ruger saw it,...if you were spending the extra change on the "sporting" Mini-Thirty, you obviously wanted quality over cost,...which by extension means accuracy too. So .308 bore was selected for this reason. The action was considered robust enough that if anyone shot .311 diameter ammo in the gun, the rifle could take it.

But Ruger underestimated how cost drove ammo sales, and the Chinese stuff was so cheap, hardly anyone bothered to seek out .308 diameter 7.62x39 ammo. And of course, a lot of young budget-minded rednecks who never read up on the difference probably had no idea there was one. And Ruger began to get a lot of rifles returned for warranty service as a result.

So at some point (I do not know the exact year) Ruger switched over to a .310 bore as a compromise. And at some point after that, they just switched over to .311 entirely to the current day.

You can see the serial number range of the Mini-Thirty here https://www.ruger.com/service/productHistory/RI-MiniThirty.html

Some say that the change in the 3-digit serial # prefix indicates when the bore changes occur. But I have no confirmation of that and I would not trust that as a guide.

[junkbug]

Mine is a mid to late 1990’s Mini-30 that I am pretty sure is the larger groove diameter. It is surprisingly accurate, but certainly no target rifle. My great irritation is that it does not always fire Russian made ammo on the first strike, but almost always on the second.

I have considered a different firing pin or heavier spring, but have not installed any yet. I think it is a great mid-range, general purpose hunting rifle.

[Outer Rondacker]

My buddy has one. He bought it about 2-3 years ago. We have only ever shot cheap wolf ammo out of it. Steel cased stuff that was bought when it was 119.99 a thousand. Shoots good no chamber issues and we have put about 400+ rounds down the pipe without an issue. It was bought as a cheap full size rifle to shoot but now with ammo prices he leaves it in the safe. Does not want to shoot up the rounds he has left.

Not sure this helps with your bore questions or not probably not

[Mr Peabody]

I bought mine a couple years ago. I shoot a lot of Arsenal 155gr gc boolits through it. I've been sizing them .311. I got curious the other day and made a chamber cast, the bore wants to measure .312. Using dial calipers isn't precise but close. So I wondered about other bolt action Rugers. Thanks

[Grayone]

I bought mine a couple years ago. I shoot a lot of Arsenal 155gr gc boolits through it. I've been sizing them .311. I got curious the other day and made a chamber cast, the bore wants to measure .312. Using dial calipers isn't precise but close. So I wondered about other bolt action Rugers. Thanks

I have one and as close as I can measure with a Micrometer it is .309. Not all runs of these guns will measure the same as manufacturing tolerances will ever be the same. I have gotten excellent accuracy out of mine with both .308 jacketed and .310 cast. Perhaps I got the best of both worlds? Anyway I have been happy with mine.