I have a M1 sales 300 fireball barrel that I have never been able to get up and running.  I form my brass from LC using a dillon rapid trim, and use redding dies to load with.  The problem I have is not all rounds chamber and those that do will not extract unfired. I was able to get some fired brass to chamber and extract when I resized just the neck but that is way too slow.  It seems to be hanging up on the neck, i even turned some of the necks down on the ouside but that didn't do it either.  I sent the barrel back once and they openned up the throat a little but it still doesn't work 100%..  I called them again and asked about conversion to 300blk, at least i could use factory ammo.  They told me the fireball and the blackout chamber they cut both require the necks to be turned inside and out for 223 brass but not 221 fireball brass.The barrel does shoot well enough but I really would like to make my own brass from 223 due to cost. Does anyone know who will  rechamber(that will work with my configuration) or a new barrel would be the next step.  I've been sitting on this project for too long, time to finish it.  Thanks

I have a 300 Fireball chamber, ( not from model 1 sales )   I have only used range brass that I cut down myself, and never had one issue.   I am using Redding dies.  Are you bumping the shell holder solid against the bottom of the die for a good Full length size?   You can also take a black marker and blacken all of the case if nessasary, then chamber, and see where hard caontacts are.  I use this method for finding distance to lands for some bullets by blackening the bullet's ogive.   Nobody has used 221 brass in years.

There is a lot of variation in fireball chambers because there isn't a recognized standard.  I have tried every possible variation of seating depth including grinding my shell holder to allow more travel.  The blackening test didn't show much but it has to be in the neck.  I also tried a small base 223 sizer then cut and sized and it still hangs up....I'm ready for it to just work.

The 300 whisper was not designed to run with .223 cases. It was designed around the .221 fireball to be necked up instead of necking down the .223. This leaves a thinner neck when sized up.

The 300BLK took that flaw away and was designed for the .223 cartridge to be necked down.

The cheapest thing to do would be to get your 300 whisper reamed to 300BLK. It costs about $50 or $60 bucks and I am sure someone could chime in on where's the best place to get it done at.

You might check with:

Paladin Machine Service
3832 Gates Ford Rd.
Kershaw, SC 29067
(803) 475-7542

I think he will ream your 300 Fireball barrel to 300 Blackout.

jonblack

I thought the blackout chamber had addressed the forming from 223 brass issue as well.  That is why I was suprised when M1S said that I would still have to turn necks with their blackout chamber.  Trying to make reloading easier for it.

The original 300 Whisper chamber was designed for 221, but has been revised.  People have been using 223 brass for a long time with JD Jones guns and all the other varients that are still a 300 Whisper.   The 300BLK is like all other chambers, as in the final quality depends on who is doing the chambering.  And sound like the Model 1 that you have has a problem and they are making excusess.  Other people have came on quarterbore.com with Model 1 barrels that work well, and only need to know what powder to use to make the carbine gas system cycle sub-sonic.   If Model 1 won't fix their problem, then Paladin, AKA Spook, Ron Williams (over in pistol threads) will fix their problem.

What about using Cerrosafe to check the actual chamber dimension?

I also use Redding dies (mine are marked 300/221 Remington) and a M1S 300 Fireball upper.  3 of my friends also have the same upper.  None of us have chambering problems (and none of use ream the necks of our brass formed from GI 5.56 brass) AS LONG AS:

1) The length of our brass doesn't exceed 1.36".  My goal is brass that's between 1.35" and 1.36", although shorter ones don't cause me problems.

2)  You don't try and crimp the reloads.  If you try and crimp the reloads, the side of the neck just below the crimp can slightly bulge out causing chambering problems.  

3)  The oal length of the loaded round is 2.26" or less.  Make sure the bullet itself is not contacting the rifling when chambered.  My reloads are typically 2.2" oal.

4)  After trimming the brass, make sure the outside of the neck is properly deburred.  Any burrs can cause chambering difficulties.  

Please post how long your brass is after forming.  

I use those same dies reloading 300 AAC BLACKOUT with no problems.

Thanks for the info guys,  i am using the 1.35" trim length and less than 2.25"oal.  When I try to extract a live round the extractor pops off of the rim and leaves the round in the chamber...I tried the bandade fix of o-ring and spring with same result, also tried different bolt too.  After the bolt is locked back I can pretty much shake the round out or give it a little pry to release it.  I may cast the chamber, not sure what that will do for me( not going to fix it, but at least I'll know why).

Well, I took the barrel off last night and got it ready for shipping.  I haven't decided we're Im going to sent it for repair.  I tried one last time to make a piece of brass that would extract with it success.  I tried:

1. Trim case to 1.350 using LC 04
2.  Debur inside and out
3.  Resized (every combination of not enough size to grinding a shellholder down so it can be ajusted to were the shoulder gets pushed back too far to be engaged by the primer)
4.  Used 208 Amax with aol of 2.150.  Bullet was not in the lands when I chambered it.
5.  Zero crimp
6. Seriously cleaned chamber and brass

Results were the same, chambered and extractor poped off when extracted.  Tipped muzzle up and round fell out of the chamber.   I quess I'm not ready yet.
Thanks for the tips.

You can try Selph Arms, LLC in Texas.  Lots of positive reviews from folks on the 300blktalk forum that got their 300 Fireball/Whisper chambers reamed out by him.