Fire forming options

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Tac-O

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I know this topic has been covered many times on this forum, but I wanted to go over it a bit here to look at my options, taking into account costs, powders I have on hand, and benefits/drawnacks of different methods.

I'm doing an AI 30-284. The virgin brass should headspace off the neck/shoulder junction with a 0.004 crush fit per Ackley's method. 284 already has a 35* shoulder and I'm going to 40* and blowing the shoulder walk out by a total of 0.010. so, there won't be a huge difference from straight 284... About 2.5-3gr.

Powders I have on hand
Trail boss
Aa5744
IMr 4227
Imr 4451
H4350

Bullets, I plan to shoot 175-200gr in the end, but local shops have 110-150gr bullets available pretty cheaply.

COW
It seems this would be the cheapest easy option and if using the lubing technique @phorwath mentioned in his FF thread, I should be able to get a full forming from 1 session and low pressure loads. With the crush fit, I may not have to lube to get a full form on 1 session.

Drawbacks
Don't get shooting practice
Messy
May not get consistent results for brass OAL change based on @Alex Wheeler post on accurate shooter forum.
Supposedly there can be some type of danger from caking or something inside the chamber or something? Not sure on this one.
I don't know if TB, 4227, or 5744 would be appropriate for COW.

Hydro die
Cheaper in the long run
Don't have to go to the range or elsewhere to FF
No wear on barrel

Drawbacks
I only use a Lee hand press for loading. Not sure if I could built a platform or something with my bench vise to mount the die.
Wouldn't be an exact match to chamber unless I send them my reamer or FF brass? Have them build it with lengthened shoulder dimension and then run it through my FL die?

Full pressure FF
Easy and get practice
With small change in case capacity, velocity might not be that far off so I could still have fun/hunt with them
Likely a full forming in 1 session?

Drawbacks
Reduce barrel life
Significantly increase costs long term

Lead FF rounds
Practice
Easy
Have suitable powders

Drawback
May not get full form on 1 session due to lower pressure?
May lead up barrel even with coated lead bullets
Costs


Thoughts? Especially would appreciate advice or experience with the faster powders I have.
 
Seating tests can be conducted during fireforming with the added benefit of barrel breakin. In my Ackley I always used full pressure loads and never used cow. I have often thought of the hydroforming dies and can imagine that would be a big timesaver. I created 257 Bob Ackley from longer brass like 3006 and 270. Cases had to be seeded down to length and then the necks physically shortened. Always took time to prepare brass before fireforming. Full pressure fireforming will leave you with the fireforme d brass you need before load development. The break in early advantage might get you up to speed before you finish development also.
 
Taylorbok said:
How much brass you doing? I pretty much decided I am doing Full pressure rounds. Figure I get to shoot/ practice. Possibly get in some preliminary load development. Plus I find a barrel speeds up after 150-200 rounds so I'll get that out of the way.
Click to expand...

MNbogboy said:
Seating tests can be conducted during fireforming with the added benefit of barrel breakin. In my Ackley I always used full pressure loads and never used cow. I have often thought of the hydroforming dies and can imagine that would be a big timesaver. I created 257 Bob Ackley from longer brass like 3006 and 270. Cases had to be seeded down to length and then the necks physically shortened. Always took time to prepare brass before fireforming. Full pressure fireforming will leave you with the fireforme d brass you need before load development. The break in early advantage might get you up to speed before you finish development also.
Click to expand...

Those are good points. I'm having a 308 rechambered that has had 100ish rounds through it, but I expect there will still be some break in to do with the new throating.

I've got about 250 pieces of brass, but only about 50 virgin.

I guess I should at least be able to do some seating tests with full pressure loads
 
I recently started annealing brass on every cycle fresh sneaked brass will form easier. I set mine to catch the first 1/8 to 1/4 inch of the body below the shoulder body junction.
This method allows for easier bumping during FL sizing.
 
I dont use full pressure loads to FF brass even new brass that just needs 1x fired I dont because I have found the web tends to expand more unless I back off about 1.5 the first FF load. How do you know what a full power load will be anyway on your 30-284 unless you've had one before.
Here's how I do it whether right or wrong but its worked well. Run atleast .003 neck tension maybe .004 jam the bullet .010-.015 into the lands and fire away.
Try a load just under max for a .284, with heavier bullet and see if they come out with a fairly sharp shoulder if not increase .5 at a time untill you do.
You need to get rounds down the barrel anyway to get through speed up and to settle down will probably take enough to quite a few brass formed, you can save some to FG for foulers also.
You can try a few different powders also will give you an idea what powder your barrel prefers.
 
L.Sherm said:
I dont use full pressure loads to FF brass even new brass that just needs 1x fired I dont because I have found the web tends to expand more unless I back off about 1.5 the first FF load. How do you know what a full power load will be anyway on your 30-284 unless you've had one before.
Here's how I do it whether right or wrong but its worked well. Run atleast .003 neck tension maybe .004 jam the bullet .010-.015 into the lands and fire away.
Try a load just under max for a .284, with heavier bullet and see if they come out with a fairly sharp shoulder if not increase .5 at a time untill you do.
You need to get rounds down the barrel anyway to get through speed up and to settle down will probably take enough to quite a few brass formed, you can save some to FG for foulers also.
You can try a few different powders also will give you an idea what powder your barrel prefers.
Click to expand...

Good point on the new brass. I had planned to do lighter end loads on virgin brass to get the web toughened up.

The capacity should only be 2ish gr more than an '06, so I planned to go with loads on the lighter end of the published loads for an '06. And I know what the maxes were for a few combos on the 30-284 bbl I did have screwed on, so I'll have a good starting place
 
with that little difference- only a few grains, I'd neck, verify rifle fit, and shoot... I've done similar pushing the 243wssm to 25wssm and didn't notice a difference at all.
 
I just found out that I would absolutely need another press for a hydro die, which I don't want to buy right now (unless I find one for $20 at a garage sale).

I may give cow a shot if I find some faster pistol powder in the store. Can't find any info on using 4227, 5744, or TB so that may not be a safe route to go. Otherwise, I'll just get some cheapo 150gr bullets and have fun :)
 
I've done the COW route. I found coffee worked better. COW tends to burn and cake up in the shoulder and had to be cleaned out with a right angle pick. Coffee is already burnt and somewhat better and easier to clean. Smells better too :)
I would also recommend cleaning every 10 rounds to keep crud out of the neck area. IME
 
Another alternative to COW is cornmeal. It doesn't seemto cake up or burn in barrel (I have used cornmeal on 500+ fire-formed cases thus far). Any fast-burning pistol or shotgun powder will do the trick.
 

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