Stiltsville
Banned
Coarse Cuban corn meal is best and smells good too.
Fireforming cases - recommendations wanted
- Thread starter P7M13
- Start date
Help Support Long Range Hunting Forum
Well, this turned out to be a chit show. At least I didn't go the range, did all the firing in the shed out back.
I used good ol' kapok - you guys remember the stuffing in old orange life jackets? I've held onto a bunch just for loading soft shooting 308s for my brother, who has terrible arthritis.
Where the clown car comes in is the primers I used. I had 20 RP cases that I had pre-primed some time ago with Win LRPs. These were a part of a batch where I had bad primer fail to fire, IIRC >50%. Here, I attempted to form twenty cases, and only seven fired.
Not enough powder, and in some, not enough stuffing for a good seal as indicated by carbon tracks on the case.
Taking the carpet roll out of the shed and uncorking the ends was a funny sight, burnt gunpowder smoke and kapok floating out like cottonwood seeds.
Here's a pic of six as formed, and what they should look like on the right.
Will take these, anneal and try again with reloading of the other 14.
Once I have the right mix, I'll do the brass. Turns out it's Lapua, not Norma.
I used good ol' kapok - you guys remember the stuffing in old orange life jackets? I've held onto a bunch just for loading soft shooting 308s for my brother, who has terrible arthritis.
Where the clown car comes in is the primers I used. I had 20 RP cases that I had pre-primed some time ago with Win LRPs. These were a part of a batch where I had bad primer fail to fire, IIRC >50%. Here, I attempted to form twenty cases, and only seven fired.
Not enough powder, and in some, not enough stuffing for a good seal as indicated by carbon tracks on the case.
Taking the carpet roll out of the shed and uncorking the ends was a funny sight, burnt gunpowder smoke and kapok floating out like cottonwood seeds.
Here's a pic of six as formed, and what they should look like on the right.
Will take these, anneal and try again with reloading of the other 14.
Once I have the right mix, I'll do the brass. Turns out it's Lapua, not Norma.
Stiltsville
Banned
Did you use Zeglin's method ?
Randy Tidwell
Well-Known Member
Personally, I am not fond of the COW (or any other filler) being fired down a good barrel. To me, you are trading one set of problems for a worst set.
These fillers harden when they are fired and are like sand paper shot down the barrel. I question whether you are saving any barrel life with that method. Know it has been done for years, I've done it too.
If you are trying to form a few hundred cases, then a donor barrel is the way to go. I have two donor barrels, 6 Dasher and 6PPC.
Other than that, I just have always had better luck shooting left over bullets (ones that are left over from other testing) with a mid range load for the parent case. You get a clean case that is formed correctly.
When I start out a new wildcat, I load up all the cases I want to fire form. Head to the range, shoot 20 or so of them.
Back to the loading bench to start load development. Next trip to the range, I fire a few more FF cases to both fireform and foul the barrel. Fire the test loads. Clean the gun, fire form a few more cases, then fire more test loads.
You will be surprised how fast you get all you cased FF, and you really aren't firing many extra rounds. You would be firing them anyway to foul the barrel after cleaning.
When forming new PPC cases, I always load up a new lot of cases, fire them in the donor barrel. I load them again for a second fire form, keep them in a separate box. During a match, I always fire at least three of them in each relay, then a couple of sighters, then record group. PPC cases rarely fire form completely on the first firing. Doesn't take long to have all them formed and ready for the next match.
The worst cases I ever formed were for my 338 Gibbs, whew! Expand 35 Whelen cases to 375, neck back to 35 with a false shoulder, then neck again to 338. Only way I could get a good case form was full house loads behind 210 grains slugs.
I formed 100 cases for a hunting rifle that will last the life of the gun.
Also, you get to break in the barrel while fire forming.
JMHO
These fillers harden when they are fired and are like sand paper shot down the barrel. I question whether you are saving any barrel life with that method. Know it has been done for years, I've done it too.
If you are trying to form a few hundred cases, then a donor barrel is the way to go. I have two donor barrels, 6 Dasher and 6PPC.
Other than that, I just have always had better luck shooting left over bullets (ones that are left over from other testing) with a mid range load for the parent case. You get a clean case that is formed correctly.
When I start out a new wildcat, I load up all the cases I want to fire form. Head to the range, shoot 20 or so of them.
Back to the loading bench to start load development. Next trip to the range, I fire a few more FF cases to both fireform and foul the barrel. Fire the test loads. Clean the gun, fire form a few more cases, then fire more test loads.
You will be surprised how fast you get all you cased FF, and you really aren't firing many extra rounds. You would be firing them anyway to foul the barrel after cleaning.
When forming new PPC cases, I always load up a new lot of cases, fire them in the donor barrel. I load them again for a second fire form, keep them in a separate box. During a match, I always fire at least three of them in each relay, then a couple of sighters, then record group. PPC cases rarely fire form completely on the first firing. Doesn't take long to have all them formed and ready for the next match.
The worst cases I ever formed were for my 338 Gibbs, whew! Expand 35 Whelen cases to 375, neck back to 35 with a false shoulder, then neck again to 338. Only way I could get a good case form was full house loads behind 210 grains slugs.
I formed 100 cases for a hunting rifle that will last the life of the gun.
Also, you get to break in the barrel while fire forming.
JMHO
Stiltsville
Banned
I'd be interested in any verified evidence (barrel a vs barrel b) that shows more bore wear from Bullseye/corn meal/poly wad fireformimg load than a full house jacketed bullet load to accomplish the same end..
Randy Tidwell
Well-Known Member
I don't have any evidence, just my opinion.
First, the residue that is left in the barrel after being burned from the powder is gritty. Push it out with a dry patch, rub between your fingers. Can't be good for the barrel.
Second, I have never gotten a fully formed case with the COW method. Always end up firing it a second time to get the sharp junctions we are looking for.
Not being argumentative, just pointing out another view of the process. Fire forming with COW (and other media) has been done forever, not saying it is wrong. Just not my choice.
If you are fire forming cases for a match rifle that will be shot 1000+ rounds, donor barrel is the way to go. That is what I do with all my target stuff.
If you are fire forming for a hunting rifle or a recreational rifle, a few extra rounds down the tube will never make a difference.
JMHO
First, the residue that is left in the barrel after being burned from the powder is gritty. Push it out with a dry patch, rub between your fingers. Can't be good for the barrel.
Second, I have never gotten a fully formed case with the COW method. Always end up firing it a second time to get the sharp junctions we are looking for.
Not being argumentative, just pointing out another view of the process. Fire forming with COW (and other media) has been done forever, not saying it is wrong. Just not my choice.
If you are fire forming cases for a match rifle that will be shot 1000+ rounds, donor barrel is the way to go. That is what I do with all my target stuff.
If you are fire forming for a hunting rifle or a recreational rifle, a few extra rounds down the tube will never make a difference.
JMHO
TRG65
Well-Known Member
- Joined
- Dec 21, 2017
- Messages
- 423
I'm forming 6.5 Addiction from a 6.5x55. I use a form die from Whidden. Here is a picture of my results. 7x fired on the right, 2 hydroformed and resized in the middle, and then base x55 case on the left. I get about 75% of the capacity increase from the hydroforming. Alcohol works much better for me than what water does.
Last edited:
Yes and no.
Powder used was AA #2 because it flows so easily. Measured to top of case, 44.7gr on my scale.
10% of that is paltry, and I knew it wouldn't do crud for me. Dug deep into the junk pile and pulled out a Lee dipper. 7.5gr of #2. Figured I'd start with that. Then thought, what if... and started incrementing the charges.
Don't have COW (haven't eaten that rubbish in >40 years). Thought about other grains, wound up using Kapok.
The disadvantage to Kapok is it's a real PITA to stuff into the case, but it does make a good packing. I've used polyester for light loads in the past, and that does melt in the firing.
In answer to @Randy Tidwell, Kapok didn't leave any crud in the barrel, and nothing inside the cases. But, heck, only seven of twenty fired.
So, I haven't figured out the best charge yet, and have tabled the testing to get some work done.
I also figured, the barrel on the 721 is junk, so I will use that as a donor barrel and do a full size on the formed cases.
I'll keep my eye out for a Rem take-off sporter barrel in 6.5 and convert that - keeping the 721 as a beater.
@TRG65 , is the 6.5 Addiction blown out to 35° shoulders? What powder do you use for accuracy loads? I'm testing RL22, but was also looking at RL26, N165, & PP4000MR.
On an aside, burn rate charts list RL26 as being slower than Retumbo, but my tests suggest it's between N165 and Retumbo, with a higher charge density.
TRG65
Well-Known Member
- Joined
- Dec 21, 2017
- Messages
- 423
it is 37deg shoulders, a little more taper than the bjai and a short .010 (I think) freebore. My OAL is 2.925 and that is .050 off my lands, so it runs more easily in a short action. I use H4831 for velocity and accuracy. It has a node about 2940 with a 147. I have a slower load with RL16 (2880) that I also use, supposedly I'll get a couple hundred more accurate rounds before the barrel is toasted. This is my match rifle so it gets a fair amount of use when we are shooting matches. I tried rl26, over 3000 fps with a 147, but I couldn't get 3 shot accuracy below .5 and wasn't consistent range trip to range trip. Retumbo is too slow max case capacity gave about 2850. H1000 gave similar velocities to h4831 but wasn't as accurate. I've heard good things about rl23, but haven't gotten any to play with myself
