Misfires in my Yugo M48A

saands · December 14, 2001, 01:54 AM

I recently purchased one of the "unissued" M48's that AIM had for awhile. I cleaned it up and took it to the range last weekend and had a rather large number of misfires with mil-surp ammo (Turkish) that has never misfired in my K98k.

Here's what I have done so far:

1. I measured the distance that the firing pin protrudes past the bolt face ... 0.060" ... my Mauser book seems to indicate .055 to .070 as acceptable.

2. I applied my post-it headspace check ... I take an unfired factory load and place layers of Post-it paper over the primer and see when it gets hard to close the bolt ... I know it isn't accurate in an absolute sense, but it does let me compare two different rifles in the same caliber ... and the M48 is actually better headspaced than the K98k that doesn't misfire.

Any ideas as to what my problem is? I didn't take the K98k with me last time, so I don't know if it was a temperature effect (it was cool but not COLD)

I'm kinda stumped here.

Thanks in advance
Saands

ps ... No ... I don't have any of the the original (misfired) primer strikes, although they were substantial. All but one of the rounds went off when I recocked and re-fired ... probably 10 failures out of 30-40 rounds.

George Stringer · December 14, 2001, 08:24 AM

Saands, .060" would be OK if you have good headspace. I think Kuhnhausen gives the standard .055" to .065" I've seen it listed by others as .060" to .065" but all these are assuming correct headspace. Some other things to check are bent firing pin, wallowed out or oversize firing pin hole, and you could have a weak firing pin spring. George

saands · December 14, 2001, 11:17 AM

I was thinking that the spring might be the culprit ... I don't recall if the rifle came with the spring compressed ... but I can imagine that if it were stored in its compressed state for 50 years, even a well designed spring might start to take a set.

Do you know of any sources for an M48 spring ... I see that the bolts are a little shorter than the K98k.

Thanks,
Saands

Joe Portale · December 14, 2001, 10:34 PM

Saands,

I see that you said you clean the rifle, but did you disassemble the bolt and clean out all the dried grease? I tinker with Mausers very often. I have found the bolts on the surplus rifles are often packed with 50 year old hardened grease. Washing with solvent doesn't always work. One of my VZ's was so cruddy that I had to dig the dried grease out.

The firing pin spring would be the second place that I would look. Wolffe Springs make replacement firing pin springs.

Have fun.

saands · December 14, 2001, 11:33 PM

Joe: Is this dreaded dried grease inside the bolt body or on the firing pin. I did disassemble the bolt, and I thought that it was really clean, although there is a little grease working its way out around the back part of the firing pin ... I wonder if there is some of that old stuff in the safety mechanism ... I think I will take it out tonight and soak it overnight in alcohol, before I order the spring ... thanks for the Wolff tip.

Saands

Joe Portale · December 15, 2001, 01:00 PM

Saands,

The grease is EVERYWHERE in the bolt assembly. Inside the tube, it cakes along the firing pin assembly (spring, cap safety). It piles up behind the breach face. I think that when the armorers greased these guys for storage, they packed the bolt assembly like a wheel bearing. If you don't catch the reference, it is pack the grease in until it starts oozing out of places.

Disassemble the bolt before soaking it. After letting it sit over night take a wooden dowel and see what you can scrape out of the bolt body.

I took a disassemble bolt sleeve to the hardware store and found a bottle brush that fit. I was amazed at what I can get out of these things.

444 · December 15, 2001, 01:29 PM

I see you appearently found the Wolff information. For those that don't have it, this is a really good web page to keep on hand.

http://www.gunsprings.com/1ndex.html

Be sure and let us know if you found the problem. I shoot that Turk ammo out of my Yugo and never had any problems. In fact it is very accurate. If you arn't having problems with your particular batch of ammo in your K98, I would think the spring would be the next logical thing to check, but then this has all been covered already. Good Luck.

saands · January 23, 2002, 05:46 PM

Well ... I cleaned the bolt COMPLETELY as suggested earlier and then I lubed it with a tiny bit of CLP and put it in the safe until the weather broke on a weekend ... that took a while. I went out and this time I brought the K98k out as a reference. ZERO misfires out of the Yugo! I didn't even shoot the K98k.

Thanks guys!
Saands

December 14, 2001, 01:54 AM	#1
saands Senior Member Join Date: November 14, 1999 Posts: 1,288	Misfires in my Yugo M48A I recently purchased one of the "unissued" M48's that AIM had for awhile. I cleaned it up and took it to the range last weekend and had a rather large number of misfires with mil-surp ammo (Turkish) that has never misfired in my K98k. Here's what I have done so far: 1. I measured the distance that the firing pin protrudes past the bolt face ... 0.060" ... my Mauser book seems to indicate .055 to .070 as acceptable. 2. I applied my post-it headspace check ... I take an unfired factory load and place layers of Post-it paper over the primer and see when it gets hard to close the bolt ... I know it isn't accurate in an absolute sense, but it does let me compare two different rifles in the same caliber ... and the M48 is actually better headspaced than the K98k that doesn't misfire. Any ideas as to what my problem is? I didn't take the K98k with me last time, so I don't know if it was a temperature effect (it was cool but not COLD) I'm kinda stumped here. Thanks in advance Saands ps ... No ... I don't have any of the the original (misfired) primer strikes, although they were substantial. All but one of the rounds went off when I recocked and re-fired ... probably 10 failures out of 30-40 rounds.

December 14, 2001, 10:34 PM	#4
Joe Portale Senior Member Join Date: June 8, 1999 Location: Tucson, Arizona Territory Posts: 715	Saands, I see that you said you clean the rifle, but did you disassemble the bolt and clean out all the dried grease? I tinker with Mausers very often. I have found the bolts on the surplus rifles are often packed with 50 year old hardened grease. Washing with solvent doesn't always work. One of my VZ's was so cruddy that I had to dig the dried grease out. The firing pin spring would be the second place that I would look. Wolffe Springs make replacement firing pin springs. Have fun. __________________ Joe Portale Tucson, Arizona Territory "Even now in heaven there are angles carrying savage weapons". - St Paul

December 15, 2001, 01:00 PM	#6
Joe Portale Senior Member Join Date: June 8, 1999 Location: Tucson, Arizona Territory Posts: 715	Saands, The grease is EVERYWHERE in the bolt assembly. Inside the tube, it cakes along the firing pin assembly (spring, cap safety). It piles up behind the breach face. I think that when the armorers greased these guys for storage, they packed the bolt assembly like a wheel bearing. If you don't catch the reference, it is pack the grease in until it starts oozing out of places. Disassemble the bolt before soaking it. After letting it sit over night take a wooden dowel and see what you can scrape out of the bolt body. I took a disassemble bolt sleeve to the hardware store and found a bottle brush that fit. I was amazed at what I can get out of these things. __________________ Joe Portale Tucson, Arizona Territory "Even now in heaven there are angles carrying savage weapons". - St Paul

December 15, 2001, 01:29 PM	#7
444 Senior Member Join Date: November 20, 2000 Location: Pahrump, NV Posts: 3,636	I see you appearently found the Wolff information. For those that don't have it, this is a really good web page to keep on hand. http://www.gunsprings.com/1ndex.html Be sure and let us know if you found the problem. I shoot that Turk ammo out of my Yugo and never had any problems. In fact it is very accurate. If you arn't having problems with your particular batch of ammo in your K98, I would think the spring would be the next logical thing to check, but then this has all been covered already. Good Luck. __________________ You know the rest. In the books you have read How the British Regulars fired and fled, How the farmers gave them ball for ball, From behind each fence and farmyard wall, Chasing the redcoats down the lane, Then crossing the fields to emerge again Under the trees at the turn of the road, And only pausing to fire and load.

December 14, 2001, 08:24 AM	#2
George Stringer Staff Alumnus Join Date: October 12, 1998 Location: Earlington KY Posts: 2,299	Saands, .060" would be OK if you have good headspace. I think Kuhnhausen gives the standard .055" to .065" I've seen it listed by others as .060" to .065" but all these are assuming correct headspace. Some other things to check are bent firing pin, wallowed out or oversize firing pin hole, and you could have a weak firing pin spring. George

December 14, 2001, 11:17 AM	#3
saands Senior Member Join Date: November 14, 1999 Posts: 1,288	I was thinking that the spring might be the culprit ... I don't recall if the rifle came with the spring compressed ... but I can imagine that if it were stored in its compressed state for 50 years, even a well designed spring might start to take a set. Do you know of any sources for an M48 spring ... I see that the bolts are a little shorter than the K98k. Thanks, Saands

December 14, 2001, 11:33 PM	#5
saands Senior Member Join Date: November 14, 1999 Posts: 1,288	Joe: Is this dreaded dried grease inside the bolt body or on the firing pin. I did disassemble the bolt, and I thought that it was really clean, although there is a little grease working its way out around the back part of the firing pin ... I wonder if there is some of that old stuff in the safety mechanism ... I think I will take it out tonight and soak it overnight in alcohol, before I order the spring ... thanks for the Wolff tip. Saands

January 23, 2002, 05:46 PM	#8
saands Senior Member Join Date: November 14, 1999 Posts: 1,288	Well ... I cleaned the bolt COMPLETELY as suggested earlier and then I lubed it with a tiny bit of CLP and put it in the safe until the weather broke on a weekend ... that took a while. I went out and this time I brought the K98k out as a reference. ZERO misfires out of the Yugo! I didn't even shoot the K98k. Thanks guys! Saands