Go-To 300 Blackout Dies

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Re: Go-To 300 Blackout Dies

Post by NiceOak » Sun Jan 24, 2021 10:01 pm

Hornady Custom Grade Dies work well for my and my brother's 300BLK ARs, however I've only loaded a few hundred rounds in this caliber. Hornady and Winchester 300BLK brass size fine. No drama with converted PMC and LC 223/556.

In general, I like the design of Hornady and Lee dies better than RCBS. I have several sets for a variety of bottleneck cartridges from each manufacturer. I like the value of Lee dies, but the machining isn't always "pretty". I swap out the locking rings on Lee and RCBS dies with Hornady ones. I like the expander in Lee and Hornady FL dies better than the RCBS "ball" design. I like the floating collar design of the Lee and Hornady seaters better than the "stem" of the RCBS.

FWIW I've been reloading for about 15 years and I only recall sticking one case in a sizing die. It was a 270win in an RCBS FL die when I was fairly new to reloading. The case was fired with a HOT load, and I didn't lube well with the paste. I switched to Hornady One Shot spray lube, and haven't stuck one since.

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Re: Go-To 300 Blackout Dies

Post by TRshootem » Mon Jan 25, 2021 12:44 am

Your RCBS die needs cases with a nice light coat of lube to work. I loathe that particular die and would give it away but I like my friends more than that. In all my years of loading for AR's and M1A's etc. I never used small base dies. Once in awhile brass fired in a out of spec chamber is encountered in older bolt and auto loaders but still not require a small base. Dillon dies are close to a small base, just a better design.

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Re: Go-To 300 Blackout Dies

Post by havoc_squad » Wed Feb 24, 2021 12:20 pm

GoneHiking wrote:
Thu Jan 21, 2021 9:06 pm
What is (are) the go-to 300 Blackout Die(s)? I ordered an RCBS small base die in this cartridge sizing to reload subsonics with mostly cut down .223 brass. In tens of thousands of rounds of rifle/pistol reloading, I've never had stuck cases like I've had with this die. Looking for another solution, no more small base. This thing is hot garbage.
Make sure you are using brass that is in the good category for converting or turn it and use the proper amount of case lube.

If your brass is out of spec on being too thick in the neck, you will have issues when it reaches the decapping head of the resizing stroke.

If it is because of the base of the case swelling too much, you'll notice it on the very end of the resizing stroke.

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Re: Go-To 300 Blackout Dies

Post by 308 Projo Hoarder » Thu Feb 25, 2021 7:28 pm

FWIW, I've reloaded a lot of M60 fired 7.62/308 brass which forces the use of the RCBS Small Base sizing die. Generous lubing (not to the point of hydraulic denting though) is required, but it works as designed.

Johnny's Reloading Bench on YouTube did a nice 3 or 4 part series on 300BO dies. He included Lee, Forster, and RCBS SB dies. It's worth a watch.

For my 300 BO I have both the Hornady and RCBS SB sets, and I haven't had a problem with either. I use homemade lanolin/alcohol lube.

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Re: Go-To 300 Blackout Dies

Post by Condor1970 » Tue Mar 02, 2021 5:56 pm

I also have used Lee dies with the factory crimp. I converted about 1,500 LC casings, all sized and loaded with the Lee dies. I did notice that the base and neck may cause the casing to be slightly set back when checking with a Lyman case gauge. However, I have had Zero issues with cambering and extraction.

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