I kinda hesitated on where to put this, but decided that the people on this board would know.  Basically, I think that there is lead buildup on the end of the chamber or throat.  Ammo for last 800+rounds has been Winchester Wildcat.  As I recall, it was getting stiff at the end of my last plinking session, but I didn't think anything of it.  At the Indy show, I picked up some super colibri, and ran about 60 rounds through it.  This bullet is just really short, but is in a long rifle case.  Because the bullet is so short, it kind of hid this problem.  Now, to chamber a full length round, the bolt has to be pounded on, and when the round is pulled out, it has marks where the lead was shaved or smeared.  When I look into the chamber, one edge of the chamber seems to be more distinct than the other.  This rifle has a relatively low round count on it < 3000 rounds.  Could this just be a sharp edge that will eventually shoot out?  Can I just get like a .243 or a 25 caliber brush and chuck it in a drill and clean it out, with the help of some deleader chemical?  

Thanks for all your help!

whisper

Not trying to tell you what to do, but I definitely don’t think you want to be pounding on the bolt handle to get a .22 LR chambered – that’s a rimfire!!! [B)]

Sounds like you’ve got some lead or powder fouling buildup in the chamber area.  Maybe this buildup is giving the appearance that the rifling is uneven in the throat.

Anyway, if it were me, I’d scrub the chamber and throat areas real good with an abrasive such as Rem Clean, J-B Bore Paste or USP Bore Paste.

Alternatively, I’d try a [b]new[/b] .22 cal bronze bore brush and a solvent.

I’ve used a power drill setup on smooth shotgun bores, but would be reluctant to try it on a rifled barrel.

Good luck!

 My experience with Super Colibri is that it really fouls up the chamber.

 I've been able to fix it by using solvent and a brasss brush...then really scrubbing the bore and chamber.


mm

Anything more specific about your experience with super colibri?  What round count to clean at?  Things you have used it for?  Max range?  Effective range?  It seems like pretty interesting ammo.

Thanks for the the help!

  Whisper,
 
I really wouldn't want to state a specific range.  From my 10/22 it hits the ground before getting to the 50 yard target at the local range.

  As soon as I fire a Super Colibri the chamber is fouled enough where it won't chamber a standard .22 LR.  It does the same in my little Ruger Bearcat.  The first time I fired it in the rifle, I didn't use the rifle again and when I got home I checked to make sure the bullet didn't lodge in the bore.  The round is that quiet.

 I use Hoppe's #9 and the brush to clean it out.  

mm

Are you sure that it was a box of Super Colibri and not just the Colibri?  Are you saying you couldn't hold over to hit something big at 50 yards?  Seems kinda funny that you say 50 yards hitting the dirt, because I have made a couble of kills at edging up on 35 yards, and I have connected at 40 yards, but it is really at its best under 50 feet.  Oh, what I was killing has just been sparrows and starlings.  I have a 24 inch barrel, just plinking at hard enough metal where it just leaves lead smears, I notice that there is a flyer about 1 in 5 shots.  A shorter barrel would be more consistent probably.

As far as the fouling problem, I thought about it for a while and decided that since it is just a really hot primer with no powder, and that primer is high explosive, the bullet is really jammed and obturated into the bore.  I guess because the bullet is so much shorter, it really gums it up because it hits sooner in the rifling.

Basically speaking, a high velocity 40 grainer probably has a [I]softer[/I] launch, although it speeds up for the first 10-14 inches of the bore, depending on powder burn rate.  Whereas the colibri and super colibri, are at max speed inside the gun, before they hit the rifling.

You thought it didn't make it out of the barrel?  Did you have hearing protection on?  As far as noise level, I would probably say that on a machine, it would be louder than my 1.77 pellet gun, but the super colibri is lower, deeper and throatier tone with more duration.  The pellet gun is really short, but high pitched and just sharp.  The super colibri sounds quieter to me, and the bird think so too.

Thanks!

p.s. I got the leading out, and I guess I have a looser gun than yours because I fired 6 of the super colibris in a row, and then chambered a standard with ease and hit a golf ball offhand @ 40 yards so that is good enough shooting for me!  

I was at the local range, so I did have hearing protection.  All I heard was the rifle's trigger and firing mechanism.

 I didn't try any holdover at all.  The target was about 12-15" off the ground.  It was Super Colibri, I still have about 20 left in the box.

 I didn't get any lead from the chamber, it was all soft fouling that came out with cleaning.


mm