My Factory crimp die question for today...

[ronbo40s&w]

Tonight i measured some more and i find my factory crimp die sizes my brass LESS than a normal sizing die (by design, i'm sure) but still enough to leave .002-.003 neck tension, based on several different brass thicknesses and measuring every which way from inside diameters to outside diameters before and after the two sizing methods, to doing the math on thickness and final bullet seated diameter.

So...here's my question:

has anybody ever used the FCD AS A SIZING DIE instead of a regular sizing die? I am decapping in station one and sizing in station two. I am wondering if I can eleiminate my brass swaging down the bullet by doing this. My experiments with setback show no need for crimp using normal sizing and minimal expanding. I am getting ready to try factory crimping a couple of rounds in station two, expanding them and seating a bullet and being done with it...and doing my usual setback testing all with a proven reduced charge.

Has anybody tried this? I am still not casting my own, but experimenting with lead reduction using the missouri bullets 18 brinell 180 gr tc bullets in my .40. The no crimp experiment worked so well, I am anxious to try this reduced sizing idea, which should make the brass last longer too if neck tension is adequate to prevent setback.

What say you, compatriots?

God Bless!

Ron

[geargnasher]

I busted out the ring in my .40 FCD, so I couldn't tell you, but it just might work. Resize a case in the seater and see if it will fall in the chamber under its own weight. If it does, bell it, seat a boolit, and see if you can shove the boolit deeper into the case by pushing the nose against the edge of a table with your fingers. If it's tight enough not to budge, load some up and go shooting. Extract and check each round from the chamber for inspection before putting it back in the magazine and firing, pay close attention to the last few in the magazine. If they're not hammering back into the cases, you're golden.

Gear

[jimkim]

IMO it is still necessary to maintain good neck tension. If your FCD sizes the boolits down, full length size with the FCD first, then follow with the regular sizing die set to size only to the point where the base of your boolit will be. This is the method I ended up using for my 45 acp ammo. It is a little odd, but it works well. http://castboolits.gunloads.com/showthread.php?t=159916

[ronbo40s&w]

Both good ideas. I found a post later last night where this is touched upon. My measurements of the brass wall thickness , inside diameters andoutside diameters of several brass are making me wonder this. On average, everything I've measured indicates .002-.003 neck tension without further sizing after the push through the factory crimp die. also, it looks like a guaranteed swaged-down using the normal sizing die which sizes the outside diameter to .418-.419, depending on the brass. Subtracting 2x wall thickness of .0115 (average of .012 and .011 actual measured thicknesses of several brass) I get .395 inside diameter using normal sizing die. Seems like a guaranteed swaged boolit. Since the fcd is leaving the outside diameter at a consistent .422, now we're talking .399 ID for .002 neck tension on a .401 boolit. I haven't tested this at all, but will make a dummy load today and see if it pushes in on my desk or sets back with chambering....hey, it may even expand the case too much to chamber whith these 18 brinell boolits...gonna be interesting. I get the typical .40 hourglass on all my reloads and can see where the boolit is, even after I stopped using the factory crimp die in staition 5 and they chamber fine/shoot great using normal sizing. the leading is what i'm trying to reduce with these hard commercial boolits. Really hoping it will cure itself when i get rolling on my own softer ones. I will keep your suggestions open for experimentation too, expecially once I cast my own. I appreciate the responses!

God Bless

Ron

[ronbo40s&w]

Okay, I just read that whole thread you linked, jimkim. Very interesting and I see you already tried the fcd sizing only. I also see I am right at the .003 per side recommended neck tension in the thread with full length sizing only. I am not all that concerned with brass life, in spite of mentioning it as a side note above. Since .40 is a high poressure round and .45 isn't, it seems unlikely my concerns warrant this experiment. I am going to reduce the charge with the most recent experiment of sizing, seating, no crimp and see what that does. The factory crimp die is snug in the plastic box until i get out the plated bullets someday...if I ever do. Again, I hope the softer boolits I will make solve the leading issue...I suspect they will.

God Bless!

Ron

[geargnasher]

Ronbo, I use a custom-made expander for my .40s that is only about a thousandth smaller than the boolit. Case springback still gives me about .003" TOTAL case tension, which is plenty. The difference between that and what you're doing safety-wise is that sizing small and expanding big leaves a nice step in the case to prevent the boolit hammering back. Now, if your boolits are 18 bhn, I doubt they'll go back too far because of the case wall taper. If you try to put .006" tension on a cast boolit, have fun with the leading unless it's about 25 BHN. .40 brass puts a LOT more crush per thousandth than just about anything.

Gear

[ronbo40s&w]

AH! okay. So I am thinking along the right lines then. I think I will go ahead and see what the original fcd sizing only gives me with a dummy round and some serious pushing against the desk..nothing to lose.

[TCFAN]

For 38 specials I have been loading fired cases using a decap die in station 1 then flair the neck and drop powder in station 2 and using unsized wadcutters lubed with LLA in station 3 seat boolit and station 4 size and crimp with the Lee FCD. These seem to shoot as good as loads reloaded with sized WC boolits and loaded in the conventional manner. Read about doing it this way on the CBA site.......Terry

[ronbo40s&w]

I tried the fcd only dummy load today....lol...not even close to enough neck tension...I actually laughed out load it pushed in so easily (still chuckling a little.) Anyway, I reduced my load back to the original load, using the full-length sizing, no crimp method that has lots of neck tension. The leading returned in big layered chunks just like before. I am convinced at this point hard commercial boolits arre the biggest factor here, being sized right at .401. I still haven't slugged my bore yet, but will when i get my mold so can make a dead soft boolit, but i bet an unsized ww boolit will cure this issue after seeing how much difference a bumped charge made. For the curious, the current and original charge was 4.8 gr universal with the 180 boolit. the charge that began to greatly reduce the leading was 5.3 gr. I have seen enough to think going higher might help, but I am not liking the increased recoil for the amount of shooting i do. The leading is managable with immediate cleaning, so i'm going to shoot them up and move on.

[geargnasher]

I told you they would lead! FL size, bell, seat, crimp, and PULL a boolit and measure it. I'll bet they're .399", and I'll bet your bore slugs .400 with dead-soft lead.

You need a custom expander spud and continue FL sizing in the regular sizer die. .40 brass is cheap.

Gear

[ronbo40s&w]

Yep. Agreed. They Do measure .399 after a slight crimp. Without crimp they are measuring at .401...with calipers...I am skeptical until i get a micrometer. I would like to use a little crimp.

I think you are right on this though. Looking forward to casting my own. The lead is easy enough to get out for now. I have a "lifetime supply" of brass that is replenished frequently. thanks for the inputs.

God Bless!

Ron

[ronbo40s&w]

Oh...where do I get the custom expander plug once I slug my bore? Thanks.

[geargnasher]

I had a machine shop make mine, but several of our member-machinists might do it for you. Why the heck do you insist on that much crimp, anyway? The only reason I turn the mouths in past straight on mine is because the chambers are tight in the front with .402" boolits, so I taper-crimp slightly to knock the front band down a thousandth at the most.

Gear

[ronbo40s&w]

What much crimp? Remember...zero crimp at the moment. the measurements are sizing only and the missouri boolit. No crimp. Crimp and seating die not even touching the brass, no factory crimp die except for de-glocking range brass prior to loading. Crimp would be for my peace of mind if I ever measure any setback with whatever boolits i end up with. At the moment there is zero crimp. The .399 was BEFORE the no crimp and factory crimp die experiments. Sorry for that confusion. I shot up the last of those today. Right now there is zero crimp and the case measures .422 at the mouth and all the way down the bullet to where the "hour glass" shape starts. Pulled bullet measures .401 with this setup. it's possible my barrel will slug at .401 and this would be no surprise if it happens.

God Bless!

Ron

[popper]

I shot ~ 1K of that MBC in my 40 before casting my own. I didn't have leading problems. You just need a bigger CB. 1st clue - you don't need any crimp to chamber. Note, my Lee moulds don't drop bigger than .403, soft are smaller.