Home Forums Hunting & Shooting Handguns Unintended consequences, Molybdenum Disulfide on cast bullets problem arose

Well, I learned a couple of things this afternoon at the gun club. The good news is that my two older Sako Action custom gopherblasters were still exactly dead on the money and still easily making itty bitty groups do that was a plus. My Browning BT-22 Lever action was also spot on and put ten shots into one ragged hole in the dead center of the bullseye at the 25 yard mark so that one is ready for Ground squirrel blasting.

But then, I began to fire a 25 yard group with mynew to my 329PD and my mini mental monsoon idea of coating the Lead cast and lubed bullets with Molybdenum Disulfide powder in the impact plating method. As it turns out, that stuff IS very slick and slippery. SO very slick that despite a pretty hard roll crimp of the case into the upper crimping groove, my revolver was locked up after three shots with the formerly normal length loads now protuding outside and past the front of the cylinder. That means, all dead STOP until I could clear it.

Part of the problem is that my handload of 10.0gr of Unique with 260gr bullets is quite snappy. I may want to back off a tad on the powder charge as these loads are not yet comfortable to shoot in the revolver. That in and of ittself may help solve the problem. I will try this along with stiffening up the roll crimp and try to crush fit the case mouth into the bullet a bit more.

It MIGHT not be possible to keep those Moly coated bullets to stay down in the case, regardless of what I do. More experimenting in soon to come and be reported on here if anyone else is interested.

Despite todays setback, I do plan to try and figure out a way to run thise Moly'ed bullets if I can.

Mark, it's not the Moly that's causing your bullets to jump forward & lock up your cylinder. It's the recoil. Mine does it with every cast bullet I've tried in it. I finally had to reduce my load to 8 grs of Unique with the 260 WFN LBT bullets I use in mine. It doesn't do it with jacketed bullets. I guess when I crimp tightly, the brass gets a better grip on the jacketed XPT bullets I use.

By the way, it never happens with my cheap little Charter Bulldog in 44 sp.

And Congrats on your new Grandson!!! Hope your feeling a little better.
More prayers on the way from TX! Neal

Are you using a Lee Carbide Factory Crimp Die? I'm running 230 cast bullets from a .41 Magnum at 975 with no movement whatsoever... I have also run a few heavier loaded cast bullets through with no problem. The FCD makes sure there is total contact between the bullet shank and the case.

CHL may be correct however...260 grains of lead generates a lot of recoil in a AirLite....

Bob

Neck tension in conjunction with the crimp holds the bullet in the case, however fast heavy recoil can over come the neck tension and crimp causing the bullet to jump forward.

If there is insufficient neck tension, no amount of crimp will hold the bullet in the case. Try taking 1-2 thou off your expander button.

The Lee Colette Factory Crimp die applies uniform neck tension to each round and thus removes one vexing variable from the accuracy equation. But, make no mistake, the Factory Crimp is adding neck tension. You can set a Lee Factory Crimp die so it pressure forms a cannelure where there wasn't one in your loaded bullet.

When we speak of neck tension we are speaking of the tension below the crimp on the bullet.

Well, I guess it is time to look for a different, better crimp die. I will see if any local fun stores have one, but I will probably have to order one.

All I used was the RCBS factory bullet seating die screwed down to cause a roll crimp into the crimping groove.

I think I will back down a bit from the load, also. 10.0grs of Unique with the 260's are right snappy, even with the 'X'frame Hogue's featuring a covered backstrap.

Thanks everyone!

PS anyone have an extra crimping die for sale or trade?

Same problem found with Ben's red. Too slippery and although none pulled to lock the gun, there was a loss of accuracy due to the primer pushing the boolit before good ignition.
You need case tension, the crimp is only an assist and no amount over just a normal roll crimp is going to help and can make things worse.
A Lee factory crimp die will ruin tension because it will squeeze the brass over the boolit and spring back, sizing the boolit and then opening too much. The lead will not spring back but the brass will.
RCBS expander dies are wrong and open brass too much and too deep.
Moly will also build up in the barrel and is a bitch to clean out.
Nobody understands crimp at all and so much on the net is so wrong it makes me laugh.
Jwp and I don't get along good but he is correct here.
If 10 gr of Unique makes boolits jump, what would you do with a 330 gr and 21 gr of 296?
Of course, the 329 was made by Mattel, light for a cap gun!

Bfrshooter is correct here, I listen if I were you Safariman.

I am listening, and need to replace my 44 Magum dies anyway as the ones I have are OLD and not Carbide or other sizing ring. Means I have to lube my cases. A brand new sporting goods store just opened up a couple of blocks from here, I think it is time for me to take a short Harley ride and check out their selection of dies and stuff

BFR, I loaded some heavy 320gr FNHC Cast bullet Technology
bullets with a hatfull of 2400 a few years ago for one of my brown bear hunts. Shot them enough in my 329PD to know that they worked, but that was ALL! I left them with my guide when I was done on that hunt. He also had a 329PD. I long ago sold the dies that I used to build those loads. When I get a good set of dies again, I will not make that same mistake, will keep them forever!

What brand of dies works best for hard recoil ammo abuse in your opinion(S). I would love to hear some suggestions. I like Hornaday Dies for rifle loading, are their handgun dies pretty good as well?

Putting on my cold weather MC riding gear, I will check back with ya'll before I head over to the fun store to see if there are any suggestions.

OK. Time for my lesson then. Why crimp at all?

C'mon BFR, you or John give me a crimping tutorial. Why bother to crimp at all?

They have all forgotten us, Magnumdood. I think I have come up with a solution, but I am going to try my experimental method first, and then write about it here if it works.

I'm running mine through Carbide Dies on a Dillan 650 press. I've never had a bullet jump the crimp & lock up the cylinder on a revolver until I bought the S&W TI .44 mag. No matter what I have tried, the recoil is just so snappy that if your shooting cast bullets, they won't stay crimped unless I reduce the load to about 850 fps.
Might as well be a glorified Airweight 44 special.
Like I mentioned before, it doesn't jump the crimp if I'm loading Jacketed Hollow Points. JMO, for what it's worth.

Thanks Chlinstructor. My previous 329PD'S did great with these exact same handloads. Since I needed a set of decent Carbide dies anyway, I went ahead and bought a new set last night and loaded up 3 cylinders full of ammo with the same load but with the new dies and a visibly aggressive roll crimp. I can tell a difference in how the bullets seat, more pressure required to get them down in the case, so I am hopeful this simple solution works. If it doesn't I will ditch the Moly and load a few more of this recipe and try 'em again that way.

Here is an un-scientific experiment:

My 44 die set (carbide resizer) has the expander stem polished down to the point that loaded rounds are "wasp waisted" so as to provide plenty of neck tension. I loaded three lubed Keith 250 gr. cast bullets in unprimed empty cases without applying any crimp. Inserted into an inertia bullet puller and gave it several healthy whacks on my block of 2x4 used for this purpose. All three bullets pulled enough by the third "whack" to have tied up the cylinder on my Smith.

I selected three more pieces of brass of the same brand, seated lubed bullets but this time with a heavy roll crimp. After the third whack on the 2x4, there was no noticeable movement of the bullet. I tried to make the "whacks" equal (I told you it was un-scientific) and added two more whacks each on the crimped cartridges. At this point, the bullet had moved slightly, but still not enough to tie up the cylinder of my Smith.

Why crimp? This is my answer........ Have a nice Easter Sunday.

I had special BR dies made for the .44 but I found Hornady New Dimension dies will equal them.
I only fold the crimps to the bottom of the crimp grooves and Lee boolits will need LESS because of the chicken scratch grooves.
I only use enough crimp to keep boolits in the brass under recoil because case tension is good. This does not work good with soft lead either. The boolit must be tough enough to expand the brass as you seat. I use water dropped WW metal at around 20 to 22 BHN.
Understand it is not your size die as all are good, it is your expander that will be wrong. If you expand too much no crimp will hold a boolit. It is just an aid to tension. Yes you need a crimp but don't go crazy.
The 329 is a light gun and has a lot of recoil so it is harder to contain boolits. Inertia is strong. Yet over crimps will not solve the problem.
A roll crimp will unfold as the boolit moves but a hard profile or FC will not and will size the boolit trying to go through the crimp. You also ruin brass life.
Even too strong a roll crimp will bulge brass under the crimp so they are hard to chamber and that will break case tension too.
Be gentle.
We will not forget you at all. Just too much other work that keeps us away.

The expander plug should be set so as to only expand the case mouth edge as to not shave lead when the bullet is seated. If the case mouth is expanded too much you will lose case tension below the crimp. The bullet should expand the case as it is seated, so as to see the outline of the bullet in the brass.
The crimp is not a replacement to good even neck tension, for heavy recoiling revolvers.