Friday, February 25, 2011

Another great tutorial from Robert(gubb33ps) on crowning barrels

Here's a REALLY handy tutorial from Robert(gubb33ps) on basic barrel re-crowning. This question gets asked a lot by modders, so here is some very good information on how to perform this mod. Thanks again Robert!


MODIFICATION 2: Crown

This adds on to the last post (which added on to the first post).
http://www.network54.com/Forum/275684/message/1296439674/2260+basic+trigger

(Yes, do have a lathe and normally recrown with one. But for this, will recrown the simplest way; one that the average guy may feel is easy enough that they will attempt it. The good news is that no matter how you foul up, can always trim ¼ inch off the barrel and try again.)

This gun actually shoots well as it is, but am going to recrown it as a tutorial anyway (and if it shoots a little better, will count it as a bonus).

1.Get the front sight off. It is a plastic part, held on by just being a press-fit.
2.A block of wood makes the best removal tool. Ju8st make sure it is clean, slide it along the barrel, and smack the front sight.
[linked image]
3.The sight will pop off. Pick it up (undamaged) as I intend to reattach it after recrowning.
[linked image]
4.Notice how the barrel has a flat spot. The sight has a spot inside that matches that flat spot, so you'll be able to put it back on straight.
5.This is what the factory crown looked like. Pretty ugly, but the results of the previous tests weren't bad at all. Pretty is as pretty does, and even as ugly as this crown is, it shot pretty well.
[linked image]
6.Chuck a round headed BRASS screw into an electric drill.
[linked image]
7.Coat the brass screw with an abrasive compound. Can use automotive rubbing compound (not polish, the more abrasive rubbing compound for well oxidized paint), valve grinding compound, even COMET cleanser will work for this. I used a fine abrasive compound made for air bursh use when etching glass mixed with lithium grease because that is what I had.
8.Place the screwhead into the muzzle, run the drill at medium speed, and rotate the drill around in a figure 8 pattern.(understand, the screw head stays in contact with the bore, you pivot the drill around in that 8 pattern.)
[linked image]
9.Take a look every minute or so. Are not trying to remake the whole end of the barrel, just the edge of the bore. Even, smooth, and polished are the key words. This was done in about 90 seconds of polishing.
[linked image]
10.Clean the barrel.
11.Reattach the front sight. All I did was add a drop of glue and tap it back on with the same wooden block that was used to take it off.

TESTING:

Charged the rifle and fired 3 5-shot groups using the same H-point pellets used in the last test.

5-shot groups
20yards
Issue 'peepsights
[linked image]

Cannot honestly say it is definitively better, but it started out petty good. Can say it is not any worse, and is likely to test out to be better, but it will take more shooting to be definitive.

Someday, will put that steel breech on the gun,s cope it, and see what it can do. But for now, it is much better than I expected it to be and it is kind of fun having a 2260 that looks pure stock but shoots this well.

Other than the time to do the two mods, the only $ expended was $5 for a 4-40 tap (used in the trigger mod). Brings the cost up to $89 and about 90 mins. of my spare time.

1 comment:

  1. Notice how the barrel has a flat spot. The sight has a spot inside that matches that flat spot, so you'll be able to put it back on straight.

    ReplyDelete