6mm Rem AI fire forming

I just place the cartridge under the extractor so that it pushes the the ejector down. I'd rather have full spring strength for positive ejection.
 
I'm with you re: using scarce resources for fire forming. I use the COW method with a Green Dot charge equal to 1/3 of a normal safe rifle powder charge (I,e.,12.3 grains for 22-250AI/250AI, 19 grains for 280AI, etc.). I always get a full fire form on on firing.

I don't fire form with bullets because I'm too impatient to get started loading for the improved round.
 
I pull the entire spring when fireforming/ on bench rifles. Nothing to do with how the case forms, but I really don't want my cases getting dinged up on concrete or dropped in the mud if possible to avoid. Means no cleaning before I load them again. Sinclair's makes a good kit for tearing down Remington style bolts, no more ejectors shooting across the room and hiding in a corner:
 
I pull the entire spring when fireforming/ on bench rifles. Nothing to do with how the case forms, but I really don't want my cases getting dinged up on concrete or dropped in the mud if possible to avoid. Means no cleaning before I load them again. Sinclair's makes a good kit for tearing down Remington style bolts, no more ejectors shooting across the room and hiding in a corner:
I could see doing that on bench rifles especially since contrete is rough on brass. Mine is for the field so I want full ejection strength. I've been catching brass for years when I don't need to manipulate the bolt fast. So it stays clean for the most part. I still clean the brass and usually wipe/ remove any carbon on the brass. Just how I've done it for as long as I've loaded.
 
Both ways work, I like full power ejection when I need it too.

The poing was that Sinclair's kit comes with the tool that holds the ejector plunger in, then you use a small punch to knock out the roll pin, and the spring and plunger slide out. I can swap the spring in and out in about 30 seconds, it's not a big to pull and replace. So all the way through load development I keep the spring out so I don't have to catch brass, then put it back in when I need it.

I think it works on Savages also, might have to disassemble the bolt to take the head out though.
 
Both ways work, I like full power ejection when I need it too.

The poing was that Sinclair's kit comes with the tool that holds the ejector plunger in, then you use a small punch to knock out the roll pin, and the spring and plunger slide out. I can swap the spring in and out in about 30 seconds, it's not a big to pull and replace. So all the way through load development I keep the spring out so I don't have to catch brass, then put it back in when I need it.

I think it works on Savages also, might have to disassemble the bolt to take the head out though.
I've been to Remington's amorer's class twice so I just free hand it. Nice tools though.
 
Don't forget that you don't always have to 'fire form' all brass to get to the near final case shape you desire.

There is the process of Hydraulic Forming which uses either water or denatured alcohol as the actuator. These dies are similar price-wise to buying Redding products but are made by either Whidden or Hornady. The front end cost is higher but can be amortized over the quantity of cases made using the process, making those cases relatively inexpensive. No bullets, powder or primers. No once fired cases, cleaning and annealing or wear and tear on your barrel and time consumed using those components.

Cheap is not always an end unto itself. It's a state of mind.

I made several hundred 6mm Rem. AI cases by loading excellent, accurate varmint loads in standard cases and shooting prairie dogs. Three shots then let that rifle cool while continuing with another rifle.

If you only need a few cases for hunting, buy a box of factory ammunition and fire form. Keep those 20 pieces to use for your hunting which should have them last quite awhile. Fire form while shooting hogs or deer if you like.

If you like tedious, load with pistol powder, corn meal or grits and tuft of something then go shoot and have a good cleaning system worked out.

Any of these methods will work and have worked for decades. Test or pick the one you like.

The importance is enjoying the process and getting to shoot something you made!

:)
 
Of the 5 ai's that i have, all shot amazing with forming loads and you could hunt with those loads and waste nothing while forming the cases. You should not have to seat bullets into the rifling to hold the case back against the boltface if it was properly headspaced as per PO Ackley. Manson headspace gauges have the .004" crush fit made into them. I am waiting on a 244ai barrel now and checked my manson gauge and it does have that made into it. It turns out I already have plenty of 6mm rem brass made into 257ai so I just need to neck it back down to 6mm. Forming already done. I'm using a Redding body die with a Lee collet die which works great. I use a LE Wilson chamber type seater. Just waiting on the barrel to get here. Its an 8 twist, 23"
 
If you ever run into .006-.008 crush fit, consider yourself blessed. You can bump the shoulder on new brass for a perfect crush fit with a standard Forster neck sizer, or use a full length sizer. Obviously, I will never shoot factory ammo in any of Ackley chambers set up with .008 crush. I have had some headspaced with .025 crush fit, which makes the neck longer in the 22/250 AI.

I also got amazing accuracy out of the fire forming loads, and never under estimate the Lee Collet sizers in how straight they size the necks. Porter precision products take the lee collet type system to a whole new level.
 
Last edited:
I have a bunch of Imp 40° cartridges. I work up an accurate fire forming load like anything else, then go bang steel, punch paper, gunt with it, etc.





23 shots fire forming to 6.5SS
20220601_063843.jpg

20220625_075141.jpg

3 Shots fire forming .260AI
20220205_082806.jpg

20220205_080851.jpg
 
260 AI is simply unbelievable in how accurate and fast it is. Looks like the 6.5 SS is a hands down winner!
My new 20" .260AI is pushing 140 Hybs @ 2911fps w. 45.3gr H4350. Pretty freaking unreal. No pressure signs until 1.3gr higher @ 46.6gr. A very slight click on primary extraction, but no signs on the cases.
 
I'm running 39.0 gr IMR 4064 with a 90 gr ELD-x in by my 6 REM AI at 3050 for a forming load. 1/2 Moa. Just run it regular until you get the number of cases you're after and then load improved loads. Easy peezy.
 

Recent Posts

Top