first time fireforming

JonathanK

JonathanK

New member
This weekend I plan on forming some 6PPCs from .220 Russians
My plan is to prep cases with FP10, expand with Sinclair .001
over mandrel, turn cases to fit chamber, load (unknown powder
yet, something I have laying around that isnt Bench, 133, or 322)
with cheap .243s, fire, and maybe turn again. Not sure of exact
diameter or thickness. Oh my chamber is .269, if any one has any
suggestions on exact diameter, thickness or a better way to do this
please me know.
Thanks,
Jonathan K
 
May I suggest that you fireform using 133 or 322 :) I'm one of those weirdos that considers the fireforming step to be paramount to good good agg'ing capacity. Fireform RIGHT and never look back. Why waste time trying to find a cheap fireforming powder? Just load up a stout load of 322 or 133 and fire away. Here's a thought, take it for what it's worth. Let's say you DO choose to reinvent the wheel and come up with another fireforming powder........ how do you find the load? where do you start? And if you DO start you'll start low to be safe, what do you do with the brass that isn't blown out properly? Lets say that you work up carefully until the shoulders are popping out the way you want them and let's say that this takes 4 or 5 tries...... what good are those partially formed cases? You can't just put them into rotation..... what I do when working up a fireform load for a new or experimental round is keep these cases and use them for setup, for finding max loads, for fouling rounds or varmints but NEVER would I consider them to be the "same" as my match loads. They'll not act the same. They'll vary in hardness and in sizing effect because they were all hit differently. Were I you I would grab me up some 68-70gr bullets, pick a load of 322 that fills the virgin case up right to the base of the neck and fire one. It SHOULD look just right, popped out nice but with rounded corners........ then you load the rest of the cases the same way and you've got your 25-30 cases ready to go, no waste. If the initial load DOES happen to be too light because you've got some slow 322 them run it up to the middle of the neck and do it again..... it should pop out perfectly and you've only "wasted" one case. Absolute WORST case scenario you may end up having to trickle charge the case as full as you can for the third go-round. I'm a bit of a Safety Geek in this regard. I've known of some hot lots of H322, some fat bullets in skinny barrels..... maybe even some bullets from another decade or with a longer than usual bearing surface, spit happens, so I can't just say "cram it clear full" although that's "probably" safe. Wasting one or two cases making SURE you're safe is reasonable attrition in my book. Especially since't this IS your first rodeo :)

On the subject of re-turning the necks. If the neck fits in for the first firing I'd hesitate to turn it smaller...... unless you're good enough to fireform with less than a thou of clearance and then RE-turn less than a thou off. This takes skill, good turning equipment, several mandrels, and a modicum of luck. Once you get over .002 of clearance ( .267 for your .269nk) you are increasing bullet cant....... the bullet WILL go down the bore with as much cant as you give it, a minimum of .001 cant when running .002 clearance. Also note that the more clearance you run the more you're working those necks. If you get up into the .003 or .004 range where you're working the brass .005 or .006 every firing you may start getting split necks sooner than you like. If you keep the clearance under .002 and the sizing effect or interference fit under .002 your necks will last forever, if you so desire.

I simply load a bullet into the neck and measure over the pressure ring for overall diameter. Shoot for .002 under chamber neck diameter for a safe and accurate setup. This should work out that a fired neck will measure .268. A bullet will be slip fit with your fingers BEFORE sizing and you will have playing room for interference fit while neck sizing. If your fired rounds measure .268 before sizing this is a good indication that your actual neck diameter matches your listed diameter. I don't think that you will go wrong using a .265 bushing with the result being a .267 loaded round.

Check the FAQ section of this site for more information re the neck turning process. Post specific questions here if you encounter challenges or have fine tuning questions.


hth


al
 
Take that jug of 133 that you left at the range on Sunday. I sent it home with Chris. Load 26.5 grains and it should work great. With any luck the case will be a jamb fit in your chamber before fireforming. Load the bullets long. Verry lightly lube the cases with imperial wax. Some will disagree with this step. If the case is as tight in the chamber as my rifle, you will want to lube the bolt lugs every other shot or so.

Get a magnifying glass and take a real good look at the first few. Look for the sharpness or the shoulder junction and signs of pressure. I use 70 grain sierras that I have laying around for fire forming.

Last thing is that you must use a ball micrometer to measure your necks when turning. Your calipers will not work. You can seat bullets and use the calipers to measure the loaded neck size and then pull the bullets and try again but what a pain that is.

I'm glad you found our game. This guy is hooked y'all. He won the 100 yard on Sunday in the club match. It was exciting for all the regulars to see. He got his comeuppance at 200 which was also kind of fun to watch. It was a great lesson about what matters in this game. Welcome to benchrest.
 
I used IMR 4064. Started out at 44 clicks and went up to 46 clicks on my Harrells.

I also ordered preprepped brass from Hoehn. Put in primers, powder and bullets and let 'er rip.

Definitely lube the lugs.
 
Thank Y'all for all the help

I have a better plan for forming now, I will use my match powder, and I have some numbers to work with. Thanks again, and Ray I'll see you August 24th, if your gonna be out there.
Jonathan K
 
Here is my take

I go through about 300- 400 cases a year. So I strive to get as efficient as possible.

Yes, I single point neck turn on an Engine Lathe. But I also have a hand tuner sitting on my desk in case I want to make up a few cases.

This ain't Rocket science. In fact, most overcomplicate the entire thing. Since you are using the .269 neck, there is certainly no need to turn twice.

Take a 220 Russian case. All I do to it is run a .0625 drill in the flash hole so the decapping pins won't stick. I de-burr the inside.

Depending on how deep you chamber is cut, you might have to bump the shoulders back so that the bolt will close. I have seen some 220 Russian cases that fit way too tight in the chamber. This is something you will have to determine by trial and error.

Expand the necks to the appropriate size for your turner, and turn the necks to where a loaded round has about .0012 to.0015 clearance. I do not measure wall thickness, since the only dimension that counts is the loaded round. Once you get the turner set, you should never have to move it again, unless you drop it, change bullets, or something.

Fill the cases with 133 to the neck-shoulder junction. Seat a typical bullet to where it jams pretty good. I put a thin film of Imperial wax on the case body, and fire. This is so the case walls will not grip the chamber walls too tight, ensuring that the case comes back against the bolt face as it should.

Then, trim then to length, and fire them again, with a regular load. They are then ready to go to the line.

Simple. As with a lot of things, many try to overcomplicate what is really a simple proccess. All of that turning twice and the sort is nothing but wasted effort.

Granted, I do not use this method exactly, as I fireform the cses first, and then do the neck turning. I just think it makes a better product, and is easier. But for now, just do what we have said. You have plenty of time later to get all creative.

Incidentally, you will be glad you went with that .269 neck......jackie
 
great info

I have some once and twice fired brass now, and thier looking good, but the shoulders are alot rounder than my brass that has been fired 15 or so times, is this OK?, also I turned the brass to the corner of the neck and shoulder, trimming just a smidge off the shoulder, because I was told it would eliminate any donuts. Also, whats a good trim to length? Sorry for all the questions, but I'm still getting set up, and have found this site to be an awesome resource with info from the best in this game.
Thanks,
Jonathan K
 
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