The Firearms Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
91 Posts
Discussion Starter · #1 ·
I have a ton of moly coated .224 bullets of various weights in my possession. I decided to try and load a few this weekend.

Here's the problem I ran into. Now, I've never crimped any of my .224 loads in the past. I've never had a problem with not crimping. Once I loaded a few of the moly coated bullets I did the old push the nose of the round against my press to see if they would slip. And, sure enough, they slipped. Slipped enough to drastically change the length.

Now, here's the question. These are non-cannalured bullets. I'm thinking that I do need to crimp but don't exactly know. Do I need a tapered crimp or rolled crimp? I'm thinking tapered because they are not cannalured. But really don't know.

Any help will be appreciated,

kevinh
 

·
Registered
Joined
·
3,588 Posts
To crimp a non-cannellured bullet you want to stick with a taper crimp or a very light roll crimp. You don't want to crimp so much that you wind up crushing the bullet under the crimp.
I don't have any specific taper-crimp dies for any of my rifle cartridges. I usually use the crimp function built into the seater/crimp die, which is basically a roll crimp.

This is a case where the Lee Factory Crimp Die would work excellent.
 

·
Registered
Joined
·
761 Posts
My Speer manual says bullets without a cannalure don't need crimping and if you do it can hurt accuracy. But I'm new so get some more responses first.
 

·
Registered
Joined
·
3,588 Posts
My Speer manual says bullets without a cannalure don't need crimping and if you do it can hurt accuracy. But I'm new so get some more responses first.
Yup, that is the general concensus for non-cannellured bullets. But proper neck tension is important for consistent powder burn (and hence velocity) too.
The slipperiness of moly, HBN, or any of these new-fangled anti-friction coatings create problems with neck tension and the bullets slipping in the cases so they do need a little help in that department.
 

·
Registered
Joined
·
21,273 Posts
be careful with the moly coating inside your barrel. It can draw moisture and cause rust.
 

·
Registered
Joined
·
87 Posts
I've shot lots of moly and am fully aware of your bullet tension concern. The best and easiest way to crimp would be the Lee taper crimp die. I have used the factory crimp die as well with good results but you need to be careful not to put too much crimp on that one as it does bite into the bullet somewhat. Extensive testing by myself and literally hundreds of others show this crimp not to impede accuracy and more often than not improve accuracy as it creates a more uniform starting pressure. Point to note as well most factory moly coated bullets have excess moly on them and should be wiped off quite briskly with a rag or paper towels and such to reduce excess moly getting into the bore. If you have questions about moly or coating your own bullets etc. just shoot me a PM . I will be happy to help.

10 Spot
 

·
Registered
Joined
·
5,238 Posts
be careful with the moly coating inside your barrel. It can draw moisture and cause rust.
Good advice dbcooper, and to expand on this a bit. Several years back the good folks at Sinclairs did a small study of the effects of moly and barrel steel. Several barrels (match quality) were sectioned after their life in bench guns rest competition was over. The barrels had, according to the Sinclair people corrosion and pitting ahead of the throats like they had never seen before. To ad to this a friend of mine that has a degree in chemistry said that moly, oxygen, and moisture make an acidic compound that is very corrosive to metal, and the effects are compounded when put under the heat and pressure of shooting. I've read pieces by some of the gun cranks that swear moly is a good thing for coating bullets. The people that I've had contact with that have used it, all swear about it now. For my 2.5 cents worth, I wouldn't let it touch any gun of mine.
 

·
Registered
Joined
·
91 Posts
Discussion Starter · #8 ·
Thanks for all the advice. I'll have to keep all these tidbits stored in my memory bank.

As far as the rust, I'll have to keep an extra eye out for moisture in the barrel and make sure it's dry. I'm not exaggerating one bit when I say I have at least 30 lbs. of moly coated bullets in .224 of varying weights. I'll shoot out at least 1 barrel on those alone. So, I kinda have to stick with the moly for now.

kevinh
 

·
Registered
Joined
·
3,588 Posts
Yup, if you do shoot moly, you do need to be aware of the chemical reaction that takes place when your firing the gun. The heat will cause the moly to break down and cause some of the sulphide to convert to a sulphite...which is what combines with water to cause the corrosion.
Tungsten Disulfide suffers the same problem as it also uses a similar disulfide carrier as Moly disulfide.
Basically, scrub as you normally would and be sure to keep your bore oiled when not in use.

Kinda sidetracking off of the OP's question but still on the subject of bullet coatings...
The newest kid on the block for friction-reducing lubes is HBN. When it breaks down it forms boric oxide and also forces some of the nitrogen into the barrel steel. Both will inhibit corrosion. It's supposed to build up much less than moly.
I'm very tempted to try HBN on bullets someday, but I just keep procrastinating. :)
We have a couple of industrial lubricants at work that contain HBN and it makes things just as slick as moly disulfide will excpet without the grey mess. Great stuff in that application and I think it would work good as a bullet coating too.
 
G

·
I have never heard of moly allowing the bullet to slip in the case. I think you first need to readjust your dies.

I know that all Hornady and RCBS rifle dies that are FULL LENGTH have a roll crimp built into them. At least that is what the techs are both companies say.

Like I said though I would readjust your dies and make sure that everything is correct. I have loaded a lot of moly bullets and none of mine have ever slipped in the case crimped or not.
 

·
Registered
Joined
·
91 Posts
Discussion Starter · #11 ·
Cpt. Tango, thanks, I'll check on the dies. I'm using Redding dies and all my FMJ bullets have done fine. I haven't crimped any of them. First chance I get I'm going to impart a slight taper crimp and hopefully that will increase neck tension enough. I'm hoping that the "slickness" of the moly is my only issue and the crimp will fix it.

kevinh
 
1 - 11 of 11 Posts
Top