My friends older and somewhat abused 30-30 is keyholing at most ranges........is there something to check or is it toast? I say new barrel, but it's so messed up, he'll get a new one before sinking money into it.
Having had some experience with this only recently, I believe one of the prime causes to be a bore of a larger diameter than the bullets. After slugging the bore, there are a number of options. There are several bullet molds that would work well, and if jacketed bullets are preferred, 303Brit/ 7.7 Jap bullets are a possibility. SW
I mentioned that and he probably won't reload. I also heard messed up crown (have not looked yet) and maybe severe copper fouling. If he gets tired of it, I'm gonna offer him 20 bucks and send it back to Marlin for a new barrel.......quite a bargin (I can fix the split stock).
Tubby take a look in the reference forum the recrown can be done by hand and is easy to do. As for severe copper fouling there are so many different solvents that work well that should not be a problem. I would at least make an attempt to clean and try it before rebarreling. Hey why spend the money if you don't have too.
What loads is he shooting? Off the shelf? Jacketed? Lead?
If lead, then I'd be looking for a bore in need of cleaning, or *maybe* a crown needing to be recrowned.
If jacketed: then again, I'd look at giving the bore a good cleaning, but otherwise, for $45 for a new barrel, sometimes that's an easier way to go.
(have to agree with nebhogger that one could use .311 or .312 bullets... but that's really a work around vs a solution)... besides, a barrel swap to a 24" new tube, and then later a reaming to an Ackley chamber - could add life to an old shooting iron.
except inthe Marines with badly shot out m-60 barrels and one Marlin 25mn any problem I had with keyholing was fixed with a good cleaning .I started with ammonia for the copper then a thorough rinsing with soapy water ,then hoppe's ,and a good new bore brush,then a patch withJB's compound and again with hot soapy water then oil her lightly and go git her dirty agin'.I once had a chance to get a friend's1894 for a price that I would have been ashamed of paying because it was throwing bullet's all over the place .I told him to give me the 30.00 to fix it he was really happy later, still had a shooter ,I still had a friend and I was thirty dollars richer of course I ended up paying for the beer and bait for catfishing the Delaware that night .shootrj2003