Weatherby .17 HMR misfire problem

C

camjohnson

Guest
I have a Weatherby .17 HMR model XXII which was purchased last year. I immediately noticed that it had about 10% misfires. I tried different ammo with the same results. I started looking at the misfired cases and noticed that the misfires all had inconsistent (very light) firing pin strikes, in fact some had barely identifiable strikes (the fired cases had normal strikes). I called Weatherby and they said to send it back. I sent it back along with several of the misfired cases (I rotated them and they fired the second time but you could see both firing pin strikes....the light one and the one that fired). Weatherby 'supposedly' fixed it and sent it back. I tried it again with the same results (10% misfires). I sent it back to Weatherby (again with 5 empty misfired cases showing the inconsistent firing pin strikes). They (Weatherby) fired 25 rounds on their range with no misfires and sent it back to me without attempting any repairs. I received it in the winter and didn't have a chance to fire it until today. I fired 25 rounds with 2 misfires. Both misfires have the characteristic light firing pin strike (barely showing an indentation). This is obviously a gun problem and not an ammo problem. However, Weatherby doesn't seem to want to fix it. Does anyone have any suggestions. It is a good rifle but I'm getting kind of upset with Weatherby's lack of abilitiy to fix it. It would seem to me that the problem is with the piston between the firing spring and the firing pin. I'm betting that it is too tight in the bolt and sometimes catches on sides when fired. I can't think of anything else that would cause this problem. Does anyone have any suggestions?
 
Cam,

I am sure you will get some good help here. Another source is on Rimfire Central. I believe your Weatherby rifle has an Anschutz 64 action. Definitely something amiss with a relatively new gun!

The problem could also be a temperature/lubrication issue. Often repairs and test firing at the manufacturer is done indoors and you most likely shoot outdoors.

Here is the link for the Rimfire Central Forum - http://rimfirecentral.com/forums/

DougF
 
additional comments

I've ruled out temperature since the problem happened last Summer, and Fall (and also this Spring). I don't take it out in the rain so humidity shouldn't be a reason. I also have the problem both before and after a rigorous cleaning.
 
Cam,

Did your rigorous cleaning include complete disassembly of the bolt?

There could be a burr on a part or foreign material inside the bolt.

DougF
 
As I stated in the original post....I tried different manufacturers of ammo with the same result...10% misfires.
 
This is definitely a possibility. I didn't 'completely' disassemble the bolt, however, I did soak it in solvent. I took it apart enough to remove the firing pin and return spring but to remove the firing spring and piston would require pressing out a pin....I didn't think this was a 'user' operation (meaning it should only be done by a gunsmith and I might not be able to get it back together). I could be wrong. If someone has experience in this area, I'd appreciate their advice (especially about getting it back together). In reply to the first poster....Yes, this is the Anschutz match 64 action.
 
camjohnson said:
This is definitely a possibility. I didn't 'completely' disassemble the bolt, however, I did soak it in solvent. I took it apart enough to remove the firing pin and return spring but to remove the firing spring and piston would require pressing out a pin....I didn't think this was a 'user' operation (meaning it should only be done by a gunsmith and I might not be able to get it back together). I could be wrong. If someone has experience in this area, I'd appreciate their advice (especially about getting it back together). In reply to the first poster....Yes, this is the Anschutz match 64 action.
Click to expand...


Try calling :
http://nealjguns.com/ Neal Johnson Gunsmithing - authorized Annie service center. It might you money but he should be able to resolve it.
 
Cam,

When you have the front portion of the bolt apart, remove the spring on the firing pin and reinsert the firing pin in the nose of the bolt. When the pin is full forward does the protrusion look reasonable for a rimfire? Did the firing pin move freely? There may be foreign material in the recess of the nose where the firing pin moves.

You already understand how to remove the front part of the bolt with the nose and firing pin. Use gloves and uncock the main spring by rotating in opposite directions the middle and back portions of the bolt. This will remove essentially all of the spring compression. Then the lateral drift pin can be pushed out by hand. The reassembly is obvious once you have it apart. I have seen burrs on the rod that forms the piston. In particular where it passes through the back portion of the bolt.

Be sure and lube the bolt parts before you put them back together. You will have to recock the bolt by hand before you can put it back in the receiver.

DougF
 
Thanks for the directions. I have checked the protrusion of the firing pin and it seems reasonable (after all.... 90% of the firing pin strikes are nice deep depressions). I did notice that if I reversed the firing pin and slid it back and forth in the hole, it did catch a little if not pushed straight in (meaning when slightly cocked). Since it is a rimfire it always get hit with an off center strike from the piston. Soooo, I took a small file and 'slightly' removed a burr from the edge. Now to try it and see if that helps. If not...then I'll take the rest of the bolt apart as you suggested.
 
burr on bolt piston

OK.... I tried the bolt with the 'minor' repair taking the 'possible' burr off the firing pin hole. It didn't solve the problem. Therefore, it was time to take the rest of the bolt apart. It came apart just as Kitsap said. I noticed marks on the piston and the piston bore had a rough mark (probably when they drilled the hole). I took some 400 wet/dry to the piston and cleaned up the rough edges and a round saw chain file to smooth out the hole. Also the piston bound up the last 1/8 inch when it was inserted. I cleaned and polished until it went all the way without binding. I lubed it and put it back together. By the way....it ain't easy going back together. It was obvious how it went but it took an extra couple hands to run the pin thru while holding the pieces together. Now back to try it and see if that fixed the problem. I'm optimistic.
 
You must log in or register to reply here.
Back
Top