300 blackout issue

[bigcountry022885]

So I have cast lead for years and this is a new problem I have never had. I am using a NOE 175gr high tec flat nose bullet and loading to 1785fps the bullets shoot amazing groups when everything comes together but I keep getting a lead ring at the throat of my bore causing the round to stick or jam any clue on the cause of this would be helpful I have just started casting for my AR platforms so this could be a common problem with them and I wouldn't know


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[Moonie]

I've read about a couple of things causing this. One is the chamber causing it and the other is seating and crimping at the same time, it can raise a ring of lead. I've never had the first issue but I have the second in other calibers so I always seat and crimp separately.

[bigcountry022885]

I've read about a couple of things causing this. One is the chamber causing it and the other is seating and crimping at the same time, it can raise a ring of lead. I've never had the first issue but I have the second in other calibers so I always seat and crimp separately.

I seat and crimp separately to so it could be my chamber


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[#40Fan]

I watched a few videos on youtube describing this issue. Always thought it was a case trimmed too short for their chamber. Never did hear an answer back from them.

[DrewSeeg]

You may need to flare your brass... I use the lee insert for a 30 carbine in a lee universal expander. Helps reduce shaving the lead while seating. I also have that noe mold ... Mine is the htc 168 with the boat tail. Shoots pretty well.

[bigcountry022885]

You may need to flare your brass... I use the lee insert for a 30 carbine in a lee universal expander. Helps reduce shaving the lead while seating. I also have that noe mold ... Mine is the htc 168 with the boat tail. Shoots pretty well.

What col do you use with that in a 300 black out


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[Moonie]

Sorry, I assumed you were flairing your brass before seating your boolits. If not you will need either an m-die from Lyman, a lee flair die or preferably an NOE expander in the lee flair die body.

[Yodogsandman]

I've only had this problem when I didn't flare the case mouth enough to allow the boolit to enter the mouth about 1/16" by hand before seating.

[fcvan]

I use a chamfer tool to bevel the inside of every rifle case for which I intend to use for cast. OK, I do them all the same, j-words feed nicely with that bevel too, and neck tension is consistent.

[popper]

What alloy? Too short a case or too long a chamber neck can allow alloy to 'bulge' when firing but the ring gets cut off by the bore. Trim to your chamber length. Soft alloy will do this. Also high seating pressure will cause the bulge at the neck. I push my stuff harder than you so use a H.T.d 3% Sb alloy.

[bigcountry022885]

Sorry, I assumed you were flairing your brass before seating your boolits. If not you will need either an m-die from Lyman, a lee flair die or preferably an NOE expander in the lee flair die body.

I use a lee universal flair die


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[bigcountry022885]

What alloy? Too short a case or too long a chamber neck can allow alloy to 'bulge' when firing but the ring gets cut off by the bore. Trim to your chamber length. Soft alloy will do this. Also high seating pressure will cause the bulge at the neck. I push my stuff harder than you so use a H.T.d 3% Sb alloy.

I'm using a 1 to 6 Linotype to wheel weight plenty hard enough and I have been playing with different COL but just can't seam to find a sweet spot I can make it longer but then I run into feed issues and I'm afraid to make it any shorter than what I am now do to compressing powder


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[DrewSeeg]

30M1 exp plug sku SE2291 ... But I would recommend the NOE expander plugs ... I have both the lee and noe. The noe is by far better but $15 vs $5. Make sure to get the correct size noe plug if you go that route. I use pure 1/5 lino powder coated and do not have leading or jamming issues. With that bullet you have to seat pretty deep as the driving band will jam into the lands if it's more than 95 thousanths out of the neck ... I believe the 300 blackout chamber is 100 thousands between the brass neck and where the lands begin. I had issues starting off with the bullet from the lee 230 ... Notice the forward driving band on the lee bullet is .303 not .309 inches for that reason. Good luck

[DrewSeeg]

I also size to 309 and run 15 grs of h110 can't remember oal but pretty far from mag length 1.975 in? I'm not near my bench ATM.

[popper]

Check your neck ID, flare tool doesn't expand the neck. Your alloy should be hard enough to resize the neck though. You should be able to to with 1:4 lino at that fps. Some BO throats are straight, some (mine) tapered, so some long seated can get stuck. Some have a large throat and small bore which causes the cutting. Lots of 40sw have this problem especially with sharp edge at the bore. I had a BO that would take 310, my good ones take 3085 max. CFEblk, 110,1680 are fine powder but 4227 isn't, I had trouble with compression using it with 168 gr. Just some ideas to help.

[bigcountry022885]

Check your neck ID, flare tool doesn't expand the neck. Your alloy should be hard enough to resize the neck though. You should be able to to with 1:4 lino at that fps. Some BO throats are straight, some (mine) tapered, so some long seated can get stuck. Some have a large throat and small bore which causes the cutting. Lots of 40sw have this problem especially with sharp edge at the bore. I had a BO that would take 310, my good ones take 3085 max. CFEblk, 110,1680 are fine powder but 4227 isn't, I had trouble with compression using it with 168 gr. Just some ideas to help.

Thanks I run my endoscope down the chamber and it's cut flat with very little taper I think that's where the ring is coming from I'm gonna play with some different molds before I give up lol


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[#40Fan]

Which mold is that you have? I have a NOE HTC310-174-SP that I'd be willing to trade you some bullets to try. 20 for 20 or more? Non-coated and sized to .309 with a Lee sizing die. Weighed and sorted to .2 of a grain. Interested?

[popper]

Several with the 40sw problem just broke that edge at the bore a tiny bit & solved the problem.

[Drew P]

I discovered that my 32-20 cowboy expander die does a great job opening the 300 cases for lead

[marek313]

I also size to 309 and run 15 grs of h110 can't remember oal but pretty far from mag length 1.975 in? I'm not near my bench ATM.

I use exactly the same recipe for my PSA 300AAC and it works great with no leading but you def have to flare cases. Without flare I'm shaving off ring of lead every single time. So far only leading I found was around gas tube where it connects to BGC it started to stick a little bit. Thats the only leading I found on my 300 and I shot about 2K of nothing but cast boolits from this upper. I picked up some FMJs to try but I'm yet to shoot any of those.