300 Blackout converted LC brass necks too thick

[Hardcast]

It's been a good while back, I bought some converted LC brass, I believe from CASTING MACHINE here on the forum. Tried loading some coated cast bullets I had puchased. Loaded rounds will not chamber in my Howa bolt action rifle. So, I thought being the coated bullets are oversize, I will load a .308 jacketed Sierra 220 RN Soft Point. Same results. A friend had given me 7 rounds of factory 300 BO Subsonic ammo, so I tried one of those. It chambered fine. Measured the case necks. My hand loads necks are several thousandths bigger in diameter than the factory load. So, I bought a .308 inside neck reamer for my Forster case trimmer. A couple days ago I finally got around to trying it. Reamed a case, which took way longer than I expected, stuck a Sierra bullet in the neck and it fell right through. Ran the case into my Redding sizer die and tried again. Same result. So I took one of mu very oversize coated bullets and ran it though a Lee .309 sizer die. Still loose in the neck. Then I tried a commercial cast 245 coated boolit from another source that measures about .310". It would not start into the neck without belling. I use a Lee universal neck expander to do this. After belling the mouth, this bullet seated fine, with good neck tension. This round chambered and fired just fine. The way I see it, the only way I can use this 500 piece bag of brass is to outside ream the necks. This would be a huge job. So I called Starline to order some factory brass. They are out and don't expect to have any for 10-12 weeks. Checked Midway and they don't have any brand of 300 BO brass. Have any of you 300BO shooters run across this problem with the necks being too thick?

[Conditor22]

Good
ADI --- PERFECTA
Aguila --- PMC
A USA --- PS
FC --- PSD
GFL ------ RA
HB --- RP
Hornady--- SSA
Hornady (nickel --- TAA
IK03 --- Tula
IMI --- TW
IVI --- TZZ
LC --- WCC
M193 --- Winchester
Norinco----- WIN NT
NOSLER --- WMA 15



Thick neck wall, bad without neck turning:

AB 556 --- L2A2
ATI --- MKE13
CBC --- MPA
CJ6 --- Norma
CJ 8 --- NPA
DNL --- PMC
FNM --- PMP
FRONTIER --- PPU
GECO --- RAM
Hot Shot---- RORG
HRTRS --- RWS
ICC --- S&B
IK03 --- SADU
IMI --- TAA
IVI --- SADU
KFA --- Wolf Brass

You could get a boolit nose sizing die from NOE or get someone to ream the chamber.

LC is one of the good brass, I've not had trouble with converted LC brass I did run into some USA brass not on either list that I think will be too thick.

[Hardcast]

Thanks for the info. I cannot see how a boolit nose sizing die would help in any way. The necks are too thick to work with a .308 bullet and the inside neck reamed case is left with a very thin neck that won't hold a .308 or .309 boolit. Factory ammo fits fine so I do not want to have the chamber reamed. A good friend is going to make me a few cases from .221 Fireball brass for me to try. I must have received an out of spec lot of LC brass.

[LynC2]

You might try running a larger expander through the neck before insidebneck reaming. A larger one would allow removing less brass. However you may need to resize the neck again. I know, it's a PITA. ��

[Gtek]

Been there done that, yet another adventure tail in the 300BO. I have one of those little outside turners and not too bad. You need one of those, a TV, and three buckets. One for the right side, one for the belly and one for the left side. A couple relaxing nights of Andy Griffith re-runs and there you go!

[brstevns]

I found with the Forster inside neck reamer of .308 I needed to use the reamer before sizing the brass. I also used some .310 cast bullets for the ones that I reamed with the case already sized, ( like you did) Hope this was of help.

[pacomdiver]

never had a problem with LC brass, converted many both blanks and reg ammo, never had a problem with them and my .311 PC 247g noe bullets in any of the 3 i reload for including a aac rem 700 and 2 ars

[Hardcast]

You might try running a larger expander through the neck before insidebneck reaming. A larger one would allow removing less brass. However you may need to resize the neck again. I know, it's a PITA. ��

My Redding 300 BO resizing/decaping die does not have a neck expander. I may see if my Lyman 30-06 decapper with neck expander will fit in my Redding die. Thanks.

[Conditor22]

I use NOE neck flare/expanding dies for all the cast I reload.

these expanders have 2 numbers: the first number is the size of the flare at the mouth second number is the diameter of the neck expander they recommend going severe thou under the boolit size your loading, I go the same size because, brass shrinks/springs back between .001 and .0015.

I would go with this one https://noebulletmolds.com/site/shop...-309-exp-plug/

You also need a LEE Universal Case Exp. Die to put the expander in.

Appoligies, I read that when you seated the boolit the cartridge wouldn't chamber

[brstevns]

If it chambers with the .310 size bullet, after flaring with the Lee Flaring tool why not just size those oversize casts bullets you mention to .310? Maybe I am missing something.

[Hardcast]

If it chambers with the .310 size bullet, after flaring with the Lee Flaring tool why not just size those oversize casts bullets you mention to .310? Maybe I am missing something.

Considering how long it took me to inside neck ream one case, I do not have the patience to do very many of them, and even if I did, Lee does not make a .310 sizer die. I could buy one for my Star sizer, but I would be getting into a lot of money and labor. I would have been so much better off to buy new Starline brass last summer instead of trying to save a few buck with the converted brass. Some lessons are expensive. Besides all this, I want to be able to load .308 jacketed bullets as well as cast. Looks to me like the only way to salvage these cases is to outside turn the necks down several thousandths. If I can find some brass with the correct size necks, it would be way easier just to buy them than to go through this hassle. Thanks for all the replies.

[popper]

Try chambering just a case. BO neck is .334? Anything larger won't fit. I neck turn for 0.011 thick to fit. Inside reaming leaves uneven wall thickness.

[beltfed]

Perhaps that Howa rifle has a Tight NEck chamber and/or a short freebore/leade.
I have had no problem with several AR 300 BO uppers with converted LC and other cases.
Using various jacketed bullets as well as 311299, 311334, etc.
You said you tried a 220 gr RN 308diameter bullet. Still a problem. Is it possible that
the RN got stopped because the nose was tight in the throat rather than the neck?
You might want to try loading a 0.308" say a 125gr spitzer bullet and see if that will work
in the un turned LC cases.
beltfed/arnie

[Hardcast]

beltfed, No, I can see the marks on the case neck where I tried to force it into the chamber. No marks on the bullet. Tomorrow, I will take some measurements and post them.

[Conditor22]

I switched to NOE for cast boolit sizing dies they have a much larger selection than lee and yes they have a 310 body Bushing (sizing bushing)

[brstevns]

Forster does make an outside case turner https://www.forsterproducts.com/prod...e-neck-turner/
I have one and it works very easily and does not take long to outside turn necks. Can also get a power adapter to use a handheld drill or power screwdriver so you do not need to wear yourself out with the hand cranks, both well worth the money.

[Loudy13]

I have cut/formed and trimmed hundreds of LC brass for 300BO and have not had any issues, is there a lip on the brass from the sizing/trimming process?

[BK7saum]

I have converted a lot of Lake City brass from various years as well as have a lot CASTING MACHINE LC13 converted brass. I also have some R-P that I've converted. Absolutely no issues with jacketed bullets or boolits sized no larger than .3095. I do not think a .311 with chamber at all. So, yes, I guess clearances are getting a little on the snug side, but all of my .309/.3095 boolits have chambered easily and shot in the Howa, Remington, and my AR, as well as a CZ 527 I used to have.

As far as your reamed case, most of the forster reamers are set up to ream a fired case, not one that has been sized. I think they make some reamers for wildcats that are for reaming a sized case where it cannot be fireformed first.

That doesn't help you if you cant chamber them to fire anyway.

I'd suggest trying a .309 lee sizer on your boolits up to .3095.

I also have a Howa Mini 300 blackout, a semi-custom remington 700, an AR, and a second Howa Mini 300BLK barreled action waiting in the box for a stock. My 12 and 13 year old girls are deer slayers with the Howa 300BLK.

[BK7saum]

To clarify, it seems that you removed too much material from the case necks with the incorrect reamer.

Your jacketed bullets should work like a charm in the brass as-is. Try a .309 sized cast boolit in a flared case before you give up completely. And if you have no use for the junk brass, I'll pay postage to get it disposed of for you.


Here is my process with converted LC brass and RP brass.

1. Size the case (I use Forster dies)

2. Expand and bell the case with an M Die 31R (this is just enough tension for a .3095 cast bullet) and not enough for a jacketed bullet.

3. Prime, charge case, seat boolit.

4. Remove flare with Lee factory crimp die to just kiss the case neck.

Good luck. Just work through the process. I cannot think of a reason why your brass isn't working unless you are trying to load 0.311" or larger boolits.

[BK7saum]

If you have to have brass ASAP, pm me and I'll see what I have that is factory brass. I just shoot the converted brass in everything and should have some factory headstamp brass put back somewhere. I don't mind losing a few pieces of the converted stuff. It was free and converted by me or cheaper to buy than factory headstamp brass.