fire forming for the 338-Lapua-inp.

[new shooter]

Tale me how much powder to used and cream of wheat to fire form my 338-Lapua-Imp. Or what you do to fire form. I have 150 cases to do. Thanks Joe

 

[RockyMtnMT]

16g green dot powder, fill with cream of wheat, pack in piece of toilet paper to hold all snug. Use pistol primer to light it. Pistol primer will show if you are too hot before rifle primer. Shoot till barrel gets warm and let cool.

Good luck

Steve

 

[new shooter]

HEAR ARE THE POWDER I HAVE I HAVENT YOUS IN 15 OR 20 YEARS. imr 4831-hercules 2400 or H335. ANY OF THEM WORK. I WOULD HATE TO GO INTO MY RETUMBO OR R-33 OR H-1000. Thanks JOE

 

[RockyMtnMT]

HEAR ARE THE POWDER I HAVE I HAVENT YOUS IN 15 OR 20 YEARS. imr 4831-hercules 2400 or H335. ANY OF THEM WORK. I WOULD HATE TO GO INTO MY RETUMBO OR R-33 OR H-1000. Thanks JOE

Green dot is pistol powder.

Steve

 

[new shooter]

I HAVE NO PISTOL POWDER. There got be away with rifle powder. Thanks Joe

 

[RockyMtnMT]

I HAVE NO PISTOL POWDER. There got be away with rifle powder. Thanks Joe

Not with cream of wheat. You can load normal 338 loads with bullet and fire form that way.

Steve

 

[HammerB1]

I just looked and Selway in Missoula has Green Dot on shelf now. 1 lb. would be plenty to do 150 cases.

As Steve said, without putting bullets down the tube, there is not a better way.

Brian

 

[azsugarbear]

If your rifle has a muzzle brake, remove it before fire-forming. TP has fibers that will get caught in the gills of your brake. They hit with such velocity that they can bend the gills or ports in your brake.

If you decide to form with bullets, I have had the best luck with a slightly reduced load with the bullet just into the lands. This seems to keep the brass from slamming back into the bolt head and gives me a more uniform shape with the new wildcat.

 

[embork]

I have a 338 lapua Rogue. 37 Degree shoulder. I use 91 grain of Retumbo at sammi specs with Berger 250 gr bullets. is accurate with this load. i use this for my long range shooting, then i can work up another load when there fire formed. embork

 

[new shooter]

16g green dot powder, fill with cream of wheat, pack in piece of toilet paper to hold all snug. Use pistol primer to light it. Pistol primer will show if you are too hot before rifle primer. Shoot till barrel gets warm and let cool.

Good luck

Steve

I put the 16 gr in then filled the case with corn meal to top then I lightly tap the case it settled down below the neck then put apiece of toilet paper. So tapping the corn meal makes it to go below the neck. Do I need to have the corn meal in the neck ? Is it all wright to tap the corn meal down. Just want to do this right. Will fire forming form the case the first time do a 100 percent or do I have to do it again. Thanks for all your help. Joe

 

[Pdvdh]

I place powder charge, cover the powder with a single layer of paper towel or toilet tissue, fill and compact with cream of wheat or corn meal to base of case neck, cover with compacted tissue to hold C-O-W / cornmeal in case; load, point in safe direction, and fire.

Removing your muzzle brake would be a good idea so the paper towel / tissue doesn't catch the muzzle brake.

The cases should blow out sufficiently on the first C-O-W firing to be formed to your chamber. You should not have to C-O-W fireform a second time, if you've generated sufficient pressure with the first C-O-W firing on the case. I would work up a load directly after the original fireforming with C-O-W. The cases will conform to the chamber more fully after you fire your first full pressure load / bullet down the bore. But the first C-O-W firing should be sufficient to get the shoulder blown out for an acceptable headspace fit of the fireformed case to your chamber.

Inspect the first C-O-W fireformed cases carefully for any splits in the shoulder area, and to see how fully the shoulder has been blown forward. If you see any splits in the shoulder (you normally won't), you'll have to anneal the shoulders before fireforming. If the shoulder doesn't 95% form, add a little powder. If you're flattening the primer excessively and getting complete shoulder formation, remove a little powder. Continue to inspect the first several C-O-W fired cases carefully for assurance your process is getting the job done safely.

 

[RockyMtnMT]

I place powder charge, cover the powder with a single layer of paper towel or toilet tissue, fill and compact with cream of wheat or corn meal to base of case neck, cover with compacted tissue to hold C-O-W / cornmeal in case; load, point in safe direction, and fire.

Removing your muzzle brake would be a good idea so the paper towel / tissue doesn't catch the muzzle brake.

The cases should blow out sufficiently on the first C-O-W firing to be formed to your chamber. You should not have to C-O-W fireform a second time, if you've generated sufficient pressure with the first C-O-W firing on the case. I would work up a load directly after the original fireforming with C-O-W. The cases will conform to the chamber more fully after you fire your first full pressure load / bullet down the bore. But the first C-O-W firing should be sufficient to get the shoulder blown out for an acceptable headspace fit of the fireformed case to your chamber.

Inspect the first C-O-W fireformed cases carefully for any splits in the shoulder area, and to see how fully the shoulder has been blown forward. If you see any splits in the shoulder (you normally won't), you'll have to anneal the shoulders before fireforming. If the shoulder doesn't 95% form, add a little powder. If you're flattening the primer excessively and getting complete shoulder formation, remove a little powder. Continue to inspect the first several C-O-W fired cases carefully for assurance your process is getting the job done safely.

I have never put anything between the powder and the cream of wheat. Seems like a good idea if they are going to get shaken and mixed up. The only other thing I do that is different is use pistol primers as they will show over pressure faster than rifle primers. With the Lapua brand case 16g has been perfect. Just pack the paper in the end nice and firm.

Steve

 

[bigngreen]

Depending on your particular case you may need a false shoulder or jambing a bullet to hold the case back against the bolt face for fire forming, if your blowing a shoulder forward without holding the case back against the bolt face your actually blowing the base of the case back to the bolt face thinning the base of the case.

 

[RockyMtnMT]

Depending on your particular case you may need a false shoulder or jambing a bullet to hold the case back against the bolt face for fire forming, if your blowing a shoulder forward without holding the case back against the bolt face your actually blowing the base of the case back to the bolt face thinning the base of the case.

Yes! You need a little stiff to close bolt so that the case is held tight.

Steve