When Slugging goes bad....

[beezapilot]

I've not done hundreds, but certainly a few, and never had this happen.

Slugged the barrel on my wife's 30-30, very clean bore, nice coat of oil, soft lead slug- first 16 inches gentle taps are moving things along then it STOPPED.

Some harder tapping did not move it at all.

Ended up knocking it out from the other end. I can see no anomalies in the bore, the "tight spot" is under the rear sight.

It is a Winchester Model 94 manufactured in 1968.

Is this something that I've been lucky to have missed over the years and is common?

[Artful]

I don't know about common but tight spots under a dovetail in the barrel are known problem when you try and force feed the cutter thru the area.

[beezapilot]

I was actually looking for a screw that had been over drilled/tapped... didn't think about upset metal from the machine process itself- thanks.

[Doc Highwall]

Another thing that will displace metal even if the dovetail was cut correctly, is driving a rear sight that has too large of a interference fit. The metal has to go some where.

[fouronesix]

Fairly common complaint about Marlin lever guns a few years ago- constriction at rear sight dovetail. IIRC- it re-ignited interest in fire lapping to remove it.

[dubber123]

You can "See" both front and rear dovetails in the bore on my Marlin Cowboy in 45-70. The barrel is pretty thin on these, but it's proof positive that the problem exists. Firelapping did wonders.

[leadman]

I've had this almost happen enough to me that I now use the egg fishing sinker or drill a hole length ways thru the boolit I am using as a slug. This allows the metal to compress easier if a spot like this is found. It can still be felt but haven't had one stop, or almost stop since doing this.

[btroj]

You learned way more than most do by just shoving a slug thru the bore.

Slugging should be about more than just knowing the dimensions of the tightest spot in the bore, which is what a soft lead slug tells you. You learned where the tight spots are. What you could do is put a slug just into the breach then tap it out. Do the same with the muzzle. Is the muzzle larger or smaller than the breach? How much smaller is the tight spot?

Fire lapping will make the rifle a better shooter with cast. Lap just enough to remove the tight spot.

[beezapilot]

Thanks for the wisdom.

My battle plan is to DRILL A HOLE in a slug. Find & measure the tight spot. Find & read what I can on firelapping. See if I can make it better.

Fine little plinker the way she is, but I'm thinkin' she might could be better.

Thanks again- Beez