Cornmeal Fireforming

stephen b · November 13, 2006, 02:30 AM

I'm trying to fireform my new 30-06 brass using Bullseye powder, large pistol primers and cornmeal. I'm up to 22.5 grains of Bullseye and the cases are not even close to the dimensions of first fired factory ammo or rounds fireformed conventionly. I've read in "Pet Loads" etc that the cornmeal method is doable. I've read that the process should start at 10% of case capacity, 4.5 grains. I started there and am ready to fire up to 30 grains of Bullseye. What's going on? I have seen no signs of excessive pressure at 22.5 grains. Anyone out there have a clue?
Thanks.

HiBC · November 13, 2006, 03:56 AM

If you are sneaking up on 30 gr of Bullseye you are looking for trouble.
If advise is given in PET LOADS and you are using 5 or 6 times as much as the recomended charge with a powder as spunky as Bullseye,please take a deep breath.
I am not too sure what sort of fireforming you are doing.
I have had excellent results forming cases with Cream of Wheat.I used to make 35 Whelens from 30-06 brass.I used a rifle primer and to my recollection,the approximate charge recomended in Pet Loads is what I used.I won't guess a charge weight,but please do back up to try Cream of Wheat.
I made a fireforming chamber insert for an old break action 10 guage using a takeoff mauser barrel for stock.Ran a 40-70 Sharps Straight reamer into it and made 40-60 Maynard brass out of 30-40 krag with good results using new brass.Once fired failed a lot.I made a series of small dippers by drilling holes in pieces of maple and snuck up on the results.I don't think I exceeded 10 grains,but,no recomendation.
If you are trying to make 30-06 brass fit a 30-06 chamber,load real loads and get some shooting practice,perhaps?.Good luch,HiBC

HiBC · November 13, 2006, 04:06 AM

I have noticed new 30-06 brass being maybe .005 undersize.
Most of the fireform work is in the thin neck and shoulder of the case.If you are trying to increase the case to fit closer to the case head,where the brass is thicker,these metods are the wrong approach.HiBC

amamnn · November 13, 2006, 10:05 PM

So that's what that explosion in the distance was!!!!! We thought it was Fort Lewis.

ammo.crafter · November 13, 2006, 10:12 PM

I shoot a .300 Belm in a Contender that is made by running a .307 Winchester thru a .300 Savage die. I reload to 10% under specs and fire in the gun with an inexpensivre bullet and all forms fine.

November 13, 2006, 02:30 AM	#1
stephen b Member Join Date: August 15, 2002 Location: Vashon, WA. Posts: 27	Cornmeal Fireforming I'm trying to fireform my new 30-06 brass using Bullseye powder, large pistol primers and cornmeal. I'm up to 22.5 grains of Bullseye and the cases are not even close to the dimensions of first fired factory ammo or rounds fireformed conventionly. I've read in "Pet Loads" etc that the cornmeal method is doable. I've read that the process should start at 10% of case capacity, 4.5 grains. I started there and am ready to fire up to 30 grains of Bullseye. What's going on? I have seen no signs of excessive pressure at 22.5 grains. Anyone out there have a clue? Thanks. __________________ stephen b

November 13, 2006, 03:56 AM	#2
HiBC Senior Member Join Date: November 13, 2006 Posts: 8,286	Too much bullseye If you are sneaking up on 30 gr of Bullseye you are looking for trouble. If advise is given in PET LOADS and you are using 5 or 6 times as much as the recomended charge with a powder as spunky as Bullseye,please take a deep breath. I am not too sure what sort of fireforming you are doing. I have had excellent results forming cases with Cream of Wheat.I used to make 35 Whelens from 30-06 brass.I used a rifle primer and to my recollection,the approximate charge recomended in Pet Loads is what I used.I won't guess a charge weight,but please do back up to try Cream of Wheat. I made a fireforming chamber insert for an old break action 10 guage using a takeoff mauser barrel for stock.Ran a 40-70 Sharps Straight reamer into it and made 40-60 Maynard brass out of 30-40 krag with good results using new brass.Once fired failed a lot.I made a series of small dippers by drilling holes in pieces of maple and snuck up on the results.I don't think I exceeded 10 grains,but,no recomendation. If you are trying to make 30-06 brass fit a 30-06 chamber,load real loads and get some shooting practice,perhaps?.Good luch,HiBC

November 13, 2006, 04:06 AM	#3
HiBC Senior Member Join Date: November 13, 2006 Posts: 8,286	More thoughts on this fireform. I have noticed new 30-06 brass being maybe .005 undersize. Most of the fireform work is in the thin neck and shoulder of the case.If you are trying to increase the case to fit closer to the case head,where the brass is thicker,these metods are the wrong approach.HiBC

November 13, 2006, 10:05 PM	#4
amamnn Senior Member Join Date: May 13, 2006 Location: WA, the left armpit of the USA Posts: 1,323	So that's what that explosion in the distance was!!!!! We thought it was Fort Lewis. __________________ "If the enemy is in range, so are you." - Infantry Journal

November 13, 2006, 10:12 PM	#5
ammo.crafter Senior Member Join Date: June 25, 2006 Location: The Keystone State Posts: 1,970	I shoot a .300 Belm in a Contender that is made by running a .307 Winchester thru a .300 Savage die. I reload to 10% under specs and fire in the gun with an inexpensivre bullet and all forms fine. __________________ "Peace is that brief glorious moment in history when everybody stands around reloading". --Thomas Jefferson