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Discussion Starter #1
Hey everyone, now that the shooting ranges are starting to open back up, I was wondering if anyone has any suggestions to help me figure out my feeding issues on my Chauchat. I have the gun out shooting and its doing about 3 round bursts and then jamming the bullet tip into the top of the chamber. Its like the back of the round is getting caught in the locking lugs, forcing the rim of the brass down and forcing the tip of the bullet into the top of the chamber, pending the cartridge. I have attached a picture of how the round seems to be jamming between the lugs, but not of the actual jam that is happening. Sorry I thought I had a better picture. From this point in the picture, the bolt forces the rim of the cartridge down and the bullet tip up, pending and smashing the cartridge. I have been using 4 different mags, which are in good condition and all seem to have the same issue. How do I know if the feed lips are good? Anyone have a spec or a way to tell? I have adjusted the feedramp, using the cam screws on the side of the gun to what I think is correct (There was no setting when I got the gun). Now, when cammed up, the feed ramp just touches the bottom of the receiver area and drops clear when the bolt carrier comes forward. That said, I have never heard of exactly how to adjust this. The jams are kind of odd. Its like the rear of the round is wide enough to get caught between the locking lugs... Anyway, I feel like I am close but hopefully you guys might have some experience that might help me figure it out quicker. I am shooting Prvi new production ammo. Any help would be appreciated.
12153 (1).jpeg
 

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Here is a pic of my mags with one showing how they dent, just on right side where the cocking handle slams into them. There is a YouTube video on why.
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Yes, look OK. Try holding up on the mag when firing, some of mine are looser then others. I am still working on mine also, my barrel drags on the outer tube. Also I was trying to use Balle N ammo in a Balle D barrel, the Balle N ammo was getting stuck and not extracting. I bought some Priv Patizan ammo and it slides into chamber unlike the Balle N ammo, but have not taken to the range yet because of the virus. Good luck and let us know if you get it fixed.
 

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Come to think of it I also had to adjust my feed ramp. When I lowered the ramp the case mouth was hanging up on the ramp as it fed into the chamber and hanging up there. Maybe try adjusting ramp again, it may have a sweet spot?
 

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Discussion Starter #6
Yes, look OK. Try holding up on the mag when firing, some of mine are looser then others. I am still working on mine also, my barrel drags on the outer tube. Also I was trying to use Balle N ammo in a Balle D barrel, the Balle N ammo was getting stuck and not extracting. I bought some Priv Patizan ammo and it slides into chamber unlike the Balle N ammo, but have not taken to the range yet because of the virus. Good luck and let us know if you get it fixed.
I have a "N" barrel, so I don't think that is my problem. The gun has the SA stamp. I have tried holding the mag up and the mag down and neither seem to make the difference.

Come to think of it I also had to adjust my feed ramp. When I lowered the ramp the case mouth was hanging up on the ramp as it fed into the chamber and hanging up there. Maybe try adjusting ramp again, it may have a sweet spot?
I have adjusted the ramp to how I think it should work... the question I have is I don't think I have ever heard of how to set the adjustment on the feedramp. That said I am fairly sure I have it correct.

I just wish I knew if it was a mag, feedramp or something else causing the issue.
 

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I have adjusted the ramp to how I think it should work... the question I have is I don't think I have ever heard of how to set the adjustment on the feedramp. That said I am fairly sure I have it correct.

I just wish I knew if it was a mag, feedramp or something else causing the issue.
Do you have the book "Honour Bound"? I wonder if it contains the information you're looking for? If it's like GOL or DP...it should have that type of info?
 

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Yep, but not with me. It will be July before I get back to look in it again. I looked for it years ago and the only thing I remember is that it was vague about how to adjust, just said it needed to be adjusted with the screws. I will look again but it will take awhile.
 

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Discussion Starter #9
Do you have the book "Honour Bound"? I wonder if it contains the information you're looking for? If it's like GOL or DP...it should have that type of info?
I do have it, I will have to reread it but I don't recall much technical data in there explaining how to get the gun running like Dolf put in his book.
 

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This might help.
The boltface recess mouth has slight raised rim around it. Make sure the outside edge of the raised rim above the bottom locking lug is beveled so the rim of the feeding cartridge doesnt catch under it. When the bolt moves forward and strips a round from the mag, the cartridge rim must move up in front of the locking lug and pass the raised rim of the boltface recess. if the outside of that section of the rim above the lug isn't slightly beveled, repro 8 Lebel ammo rims will catch and stop the rear of the round from rising past the boltface rim due to the soft brass. Stopped by the boltface rim, cartridges are angled too high and the tip of the bullet hits the breechface or the top of the mouth of the chamber and won't enter.
The radius on the rim edge of PRVI repro ammo is the wrong spec compared to vintage ammo which has no problem moving past the boltface rim on feed.
FWIW
 

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Rim thickness does not matter with this issue.
Compare the rim radius and it's shape between a vintage 8 Lebel rim and a PRVI rim. The vintage 8 Lebel rim radius looks like it is is close to half a parabola with the gradual curve leading to the sharper curve at the rim which seems to allow the round to move past the boltface rim. The PRVI is a very small quarter circle radius.
I have fired a lot of '48 dated vintage ammo in these guns and never had the kind of angled jam as noted above until using PRVI. Looking closely at one of those PRVI jams it was clear that the rim had caught under the boltface rim. When I slightly beveled the outside of the boltface rim above the lower lug on feed, the jam with PRVI never happened again. Vintage 8 Lebel has hard brass and the PRVI is soft which also does not help. FWIW
 

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Discussion Starter #14
This might help.
The boltface recess mouth has slight raised rim around it. Make sure the outside edge of the raised rim above the bottom locking lug is beveled so the rim of the feeding cartridge doesnt catch under it. When the bolt moves forward and strips a round from the mag, the cartridge rim must move up in front of the locking lug and pass the raised rim of the boltface recess. if the outside of that section of the rim above the lug isn't slightly beveled, repro 8 Lebel ammo rims will catch and stop the rear of the round from rising past the boltface rim due to the soft brass. Stopped by the boltface rim, cartridges are angled too high and the tip of the bullet hits the breechface or the top of the mouth of the chamber and won't enter.
The radius on the rim edge of PRVI repro ammo is the wrong spec compared to vintage ammo which has no problem moving past the boltface rim on feed.
FWIW
Thanks very much for the reply. This sounds like and makes sense with exactly what is happening. I checked my bolt at the spot of the red arrow in the picture which I assume is the spot you are talking about. It does feel like it would catch the rim. I tried a piece of brass and I could see it happening. I will bevel that rim and see if that does the trick. Boy if this it... that would have taken forever to figure out. Thanks for the help!

IMG_20200515_083805.jpg
 

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Discussion Starter #16
Sure, I am probably just going to take my dremel and the polishing wheel and break the corner so that rim does not catch. If it works, I will be sure to report back. If it does not work, I will need more help most likely anyway. :) I have it almost shoot! So close...
 

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If you bevel it and that works can you post a pic of the beveled bolt face?<
Just a head's up: the boltface is NOT beveled. Only the underside of the raised rim above the "lower" bolthead lug on feed is relieved of the sharp outer edge with a slight inward bevel starting below the rim. When the feeding cartridge rim is rising up to pass by the front of the boltface, the outer sharp edge of the boldface narrow rim can catch the cartridge rim as it starts to slide upwards. The cartridge is angled sharply upward at this point and if the rim cannot pass by the boldface the forward momentum of the closing bolt jams the rear of the cartridge forward and the tip of the bullet hits the top of the chamber mouth.
This appears to me to be the feed problem with Matt's gun.
In the cases of a number of Chau Chats that I reactivated, out of over two dozen, the feed was completely jammed on every round due to this problem with the PRVI ammo. It had never happened with the vintage 8 Lebel rims for the reasons I noted above. FWIW
 

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Discussion Starter #18
Bob, I think I am following you on that. I think you can even see the brass marking the bolt right where my red arrow is above. That raised rim is catching the rim of the round and keeping it from popping up into the chamber. So basically its getting caught on the bolt as shown in this picture. I just need to break this edge so the rim will slide past and up onto the bolt face.
IMG_20200515_172051.jpg
 

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Bump to top for friend. He said "Chauchat failure to feed issues" no ****, that is an understatement there must be a million failure to feed issues with this gun. I only bought a Chauchat because I meet a guy whose Chauchat worked perfect, he was either very good or very lucky. I thought that worked good, and cheap guns too, I am going to buy one! 20 years later and I am still trying to figure It out. This is a gun for people who like to tinker in their shop not shoot on the range.
 

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Discussion Starter #20
To update my part of the thread, I think Bob got the problem perfectly. I took the edge he was talking about off and did not have that problem again! That said I found that I have a week ejector and every other round was failing to leave the chamber and so I was unable to run it well enough to really confirm things yet. That said, I think I solved the issue with a stronger spring, so I hope to find out if the problem is completely solved, maybe as early as this weekend.
 
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