some fail to fires in Yugo 8mm surplus ammo using Rem 700

[ockhamsrifle]

Seeking advice on improving the ignition of mid-1950 era Yugo 8x57mm ammo in Rem 700. Tried a heavier firing pin spring and it didn't seem to help. Headspace is very good (on the short end of specs). Same ammo fires 100% in two different Mausers (Czech & German made). I know this isn't a common topic for this forum, but there seem to be a lot of real smart guys here and I am stumped. I tried some other forums where I thought the members were more likely to shoot cheap surplus ammo, but with no luck, they didn't know the answer.

Thanks for your patience.

 

[spclark]

First I'd compare the fp indentation among fired cases from all 3 rifles. Mark each case so you know which rifle belongs to which case. If the Remington's fp indent is markedly larger in diameter or shallow compared to the other two, you have two options:

1.) Have a gunsmith check the fp protrusion...

(If you're not the original owner of this rifle the fp protrusion may be shorter than it should be. The instruction insert for a Rem 700SA Wolff spring I have suggest the protrusion should be no more than .065".) ...or just buy a new fp:

http://www.superiorshootingsystems.com/SPEEDLOCK-Speedlock_Firing_Pins.html

2.) Have the bolt bushed, which usually requires a slight resizing of the fp tip for best fit. The smaller tip will impact the primers with greater force (less surface area) which may be all it takes.

Since you already tried a stiffer spring and you believe the headspace to be "in-spec" you're already 75% closer to figuring out the problem....

 

[Robert]

First I'd compare the fp indentation among fired cases from all 3 rifles. Mark each case so you know which rifle belongs to which case. If the Remington's fp indent is markedly larger in diameter or shallow compared to the other two, you have two options:

1.) Have a gunsmith check the fp protrusion...

(If you're not the original owner of this rifle the fp protrusion may be shorter than it should be. The instruction insert for a Rem 700SA Wolff spring I have suggest the protrusion should be no more than .065".) ...or just buy a new fp:

http://www.superiorshootingsystems.com/SPEEDLOCK-Speedlock_Firing_Pins.html

2.) Have the bolt bushed, which usually requires a slight resizing of the fp tip for best fit. The smaller tip will impact the primers with greater force (less surface area) which may be all it takes.

Since you already tried a stiffer spring and you believe the headspace to be "in-spec" you're already 75% closer to figuring out the problem....

SPClark,
It is here question of Berdan 5,5mm primers, probably with thick cups for MG use… I do not think reducing the FP tip diameter would solve the problem, as there must be a relation between the solid anvil and FP tip radiuses. Ignition flame flow is totally different than on Boxers.
If everything else correct, and bearing in mind that 98 protrusions are originally smaller than .065’’ (as intended for Berdans), but with much longer FP falls (then impact energies) than most actual commercial actions (10mm for the 98 and only 6,35mm and a lighter moving part) for the Rem 700), the only solution I can see is a (much) stronger spring…

Ockamsrifl:
Have you tried to recock and fire again on a round who did not fired on the first impact? If it then goes, the protrusion is not in question, but it is the impact energy instead?.
If you do not want to modify your Remington (why the hell have it in this obsolete calibre?), then, shoot your surplus ammo in your 98s!!!. Moreover, this ammo is most likely steel jacketed, not very, very good for modern barrels, definitely not at all for stainlesses.
R.G.C

 

[Travelor]

Interesting - a Remington 700 in 8mm Mauser.

 

[p17enfeild]

reminton did a limited run about 2 or 3 years back they were classic bdl

 

[mj2evans]

50s vintage Yugo 8mm is known for being hard to set off. Guys shooting it in 1919a4s have been know to make a firing pin just a tad longer than normal just for that ammo. Primer tends to be set a little low and is hard. I gave up on it - the 70s Yugo ammo is excellent but hard to find.

 

[ockhamsrifle]

SPClark-Rem firing pin indent is much shallower and smaller diameter (possibly because shallower). Also fired 1983 Hirtenberger (boxer primed) in Rem 700 and fp indent is very similar to the mauser fp indent in the 1950s Yugo ammo.
How do I check fp protrusion?

Robert-recocking and hitting again will always set it off. Can I modify it to shoot the harder primers and standard US primers? I bought it because the 1950s Yugo ammo was 7 cents a round and I am learning to shoot a rifle from standing, sitting and prone positions and I thought it would be good practice ammo. It is not steel jacketed but gilding metal jackets same as the modern bullets. It is corrosive and needs to be cleaned with water and then normally.

mj2evans-how much longer on fp?
Thanks for the responses, I really appreciate the great input

 

[Robert]

Ockamsrifle,

I would then go no further than questionning the FP impact. most likely, having the FP spring chnged for a stronger aftermarket one would be the only thing to do. Have however for safety the protrusion checked at the same time, but I do not think this necessary.

We have shot here quantities of wartime corrosive ammunition, and never used water, who will certainly do nothing good for cleaning this fouling. It is not black powder or cordite combustion residues who are to be eliminated...
R.G.C

 

[ockhamsrifle]

I don't claim to be an expert, but as I understand it, this ammunition I am using is corrosive because potassiium chlorate was used in the primers to supply oxygen for a "bigger spark". After the oxygen is given up during firing the potassium chlorate becomes potassium chloride (which by the way is sold in the stores for people on low salt diets). The potassium chloride attracts water from the air and the combination rusts the steel in the barrel. Hot water poured down the barrel before and after normal cleaning (which gets rid of the normal residue/fouling) dissolves and pushes out the potassium chloride. I'm told that in desert areas this is not necessary, but I live in the midwest.

I'll see if Wolfe has an even heavier fp spring. Thanks to all that helped.

 

[mj2evans]

The water does not have to be hot - that just helps the barrel dry faster. All the water is doing is flushing out the salts, a little soap will help break the surface tension (ammonia is *not* required as many believe). Corrosive is no big deal in a bolt gun, I just keep an old spray bottle of water with a drop or two of dish soap it in - two or three squirts and you are on to cleaning like usual. Now it can be a real pain in a gas gun but if the price is right I shoot it for fun.

 

[Robert]

I don't claim to be an expert, but as I understand it, this ammunition I am using is corrosive because potassiium chlorate was used in the primers to supply oxygen for a "bigger spark". After the oxygen is given up during firing the potassium chlorate becomes potassium chloride (which by the way is sold in the stores for people on low salt diets). The potassium chloride attracts water from the air and the combination rusts the steel in the barrel. Hot water poured down the barrel before and after normal cleaning (which gets rid of the normal residue/fouling) dissolves and pushes out the potassium chloride. I'm told that in desert areas this is not necessary, but I live in the midwest.

I'll see if Wolfe has an even heavier fp spring. Thanks to all that helped.

Sorry, I may be naive, and I always thought usuall cleaning methods and bore protection was all what needed for cleaning barrels shooting corrowive primers.
We used all kinds of those left here in 1944, german, polish, czech; yugo (the polish were even mercuric).
I have seen normal cleaning done for decades with no damage for the barrels.
The practise of hot water was not in the german practise methods, while it was for the SMLEs sshooting Cordite.
R.G.C

 

[Kenny474]

I have quite a few Mosin's, and I shoot a LOT of corrosive ammo every year. Probably in the 3000-4000 round range through 5 guns. I have always done a pre-flush with boiling water and used Hoppe's to clean with, as it will neutralize and remove the corrosive agents. I have on occasion used a bit of Windex as well. The hot water seems to make cleaning much easier, so it has benefits beyond removing the corrosive stuff as well. I also use a patch of T/C's Bore Butter after cleaning, and it makes the next round of cleaning much easier with no loss of accuracy.

As far as the mis-firing is concerned, as others have stated a heavy FP spring will likely solve your problem. The Berdan cups on some surplus are very hard, as they were used in MG's and the thick cup helped prevent slamfires. The old surplus guns have a very stiff FP strike to get by it. I have read of a few other solving this problem in the 700 with the spring as well.