MOLY IN A GAS GUN

[4xforfun]

Well, I just pulled the trigger (no pun intended) on a Rem r-25. I did a little soal surching, decided I was going to reload, so I ended up withh a 7mm-08. Got a screaming deal on one. I have a bunch of 120, 140, 150 Nostler BT's, a bunch of 168 and 180 JLK's, and some assorted other bullets sitting on the shelf already. My problem is that they are ALL Moly plated (NECO).

Are there any issues with running moly in a gas gun?? I could just buy more bullets or tumble these in corn cob to strip off the moly.....BUT I LIKE MOLY.

Also, any reason to spend the big $ on Norma or Nostler brass, or go with the cheap Win/Rem stuff?


What say you??
Thanks,
Tod

 

[FroggyOne2]

nope, no problems, you will be fine.

 

[jonbearman]

I have been shooting moly for years in all my gas guns.The only draw back is they clean easier.LOL

 

[4xforfun]

How about the brass......go for the gold or buy the cheaper win/rem?

 

[jlmurphy]

I made the mistake of using my collection of old Lapua .308 brass ,big mistake, it runs to the max case head diameter of industry standard and I hadn't paid attention to case head dimensions during resizing. I had to drop out of a tactical competition when it repeatedly failed to fully chamber the oversize brass. I bought 500 pieces of Win. brass, shoot once and resize with small based die.

 

[KevinThomas]

Tod,

Looks like I'm headed against the grain here (sorry guys), but yes, there's some potential problems with using moly in gas guns. In the interest of full disclosure here, I'll tell you flat out that I'm not a moly fan in any circumstances, but there's some extra special reasons to avoid it in gas guns. A friend of mine, who's an excellent M14 gunsmith, coined the term "moly migration" after seeing some damage to guns he'd built which had subsequently been used with molyed bullets. In examining these guns, he determined that moly had been worked back onto the chamber walls during the feeding and firing process, eventually resulting in excessive bolt thrust and some peened lugs. He also saw some functioning problems once the moly found its way into the gas system. I don't know if that would be a problem with the AR type system, but it's something to be aware of.

I'd say don't do it. There's really nothing to be gained here, and there are some serious potential problems to be aware of.

 

[people]

I cannot say I have had any problems at all. I have shot out a couple tubes along the way. While it is dirty and seems to leave a coating of molly on everything it comes close to I cannot say it hurts to be used. Many will tell you it will trap water underneath it and rust the metal. I live in ND and that does not seem to be an issue here. I also shoot my rifle more than others tend to.

I say shoot it up. If you want to change once those are gone then do so. If you want to keep shooting them after that do so. Barrels are kind of cheap. Remember if you do not ever shoot your rifle you will never need a new tube. I like shooting so new tubes are just a way of life.

 

[Rookie]

All my AR guns get fed Moly bullets. No problems here.

 

[flatlander]

Could be there's enough difference in gas systems of the M1A/M14 & ARs to mitigate the problems Kevin spoke of - what I do know is that I've shot-out several AR15 bbls. in NRA HP competition using moly'd bullets exclusively without having any issues. To quantify that statement, I've logged well over 30,000rds. of moly'd bullets in both service rifle (20") & match rifle (26"-28") AR bbls.

I didn't get into the AR10 game until more recently, but have now built four in: 6XC, 6.5x47 Lapua, 7mm-08/AR30, and 308. Since I got tired of the whole moly process, I've switched to HBN, but am shooting a mixture of left-over moly'd and freshly BN coated bullets in these rifles. Have yet to reach the 1000rd. count on any of them, but have seen no problems or issues with coated bullets.

 

[KevinThomas]

Dennis,

entirely possible, and I don't have a definative answer where the ARs are concerned. The feeding and throating of the M14 family is quite different than that of the AR series, especially in light of the lug situation. Certianly worth keeping an eye on for a while to see what develops.

 

[DaveWhite]

I would shoot up your inventory of molyed bullets. I would also consider obtaining some Lake City Brass, as it seems to hold up better than the commercial brass in gas guns. If you have not read Glen Zediker's writings on gas guns, it is a great resource.

Hold Center.

 

[4xforfun]

It sounds like moly shouldn't be a problem. I ordered my brass, cleaning supplies, ect.....yesterday. Just need to pick out a scope, and rings....Not sure weather or not I will cheap out on a scope for deer season, and then mount up My 5.5-22-56 NSX for the remaining 11 months of the year, or buy a Leupold 4.5-14 VXIII for permanent duty.

 

[learningshooter]

I don't know anything about Moly much except that it is highly debated. I've worked long and hard to accquire some top shelf equipment. Until something becomes industry standard, I stay away from it. If guys like Tubb and Tony want to play with it on a sponsors dime, let them. But I like to stick to what proven.

 

[jonbearman]

I think the biggest problem is over use of the moly.I have seen major manufacturers using so much on the bullets that I had to tumble them in clean corn cob media to remocve the excess so as not to have build up.When I am done the bullets look like they have a thin shiny surface.I have never seen migration with my process.I will share my process with anyone who wants to learn my way,it works.PM me if you want the details.

 

[Dans40X]

The "Moly Migration" coined from the excellent M14/M1A gunsmith of whom Kevin references-

Moly will migrate into/thru a chamber/gas system whether it be gas impingement/piston that the Bbl was headspaced at +.010" to +.015" & sent out the door.

Too many 12oz curls while attempting to bbl/chamber a customers rifle isn't/wasn't wise on the part of this so called excellent gunsmith.

 

[Klong]

I have shot more than 10,000 rounds through AR15's in highpower rifle competition with no ill effects. Barrels do not seem to last any longer than naked bullets, but I can get 100 fps faster velocity for 600 yards.

 

[KevinThomas]

Dans40x,

The migration he spoke of had nothing to do with the gas system, but the shifting of moly from the bullets, to the feed ramps and eventually back to the case necks, body, and ultimately, the chamber itself. The problems resulting had to do with excessive peening or battering of the lugs, as they were apparently taking far more bolt thrust than is transmitted from firing a "dry" chamber. In extreme situations, this is akin to firing proof loads every time one pulls the trigger. in short, the moly was doing what moly does best; it was reducing friction. Unfortunately, some degree of friction is a desireable, even neccessary factor in may areas of a firearms proper functioning. In this case, that reduction of friction is translating itself into excessive wear on some parts which were now taking more of a hit on every round fired than they were designed to.

The guy's shot himself into both the President's Hundred and a Distinguished Rifleman's badge (and shooting against ARs at that) with M14s that he's built. He knows his business well enough that he's still building them for the US military. So between the two you, I think I'll stick with his observations.

 

[Dans40X]

Kevin,
Care to comment on the .22-250 & .260 Galactic Gun M1A's your so called excellent gunsmith debuted several years ago!!
(neither made it past the 200yd Standing Match-22rds)

I've repaired too many of Ken's screw ups!

 

[FroggyOne2]

Is this thread turning into another pissing match?

 

[KevinThomas]

FroggyOne2,

Nope, clearly an agenda here. Takes two to have a tug o' war, and I'm not picking up the rope.