Flash out of ejection port with TAC powder, should I be worried?

[Skyfire1201]

Hi all,

I'm relatively new to reloading and noticed something strange while developing my XM193 clone in preparation for the next shortage. Using the TAC power, from time to time I can see noticable flash existing the ejection port. The bullet is 55gr FMJ, Rem 7 1/2 primer, and TAC powder by the book. It's not consistent and doesn't seem to be related to powder charge. The gun is a factory midlength BCM upper. Can someone tell me what's going on and whether I should be worried?

Thanks in advance!

[markm]

TAC is a little on the slower burn end of the spectrum for .223. Especially with 55 gr bullets. You're likely getting flash out the port because the powder is still burning up by the time the bullet hits the gas port.

I used to shoot TAC out of an SBR, and with a card board barricade/cover piece, I could see peppering in the card board from un-burnt powder kernals. You could try a different/faster powder. WIN 748 would most certainly eliminate what you're seeing. It doesn't even flash out the end of the barrel.

[shootist~]

I use TAC (24.6 grains) & Rem 7 1/2s in a 16" & 14.5" mid-length /W 55 Hornady FMJs and have never noticed any flash at the ejection port. (Never looked for it, though.)
Don't see it with 24+ TAC grains and Nosler 77s either.

[Skyfire1201]

markm, thank you for the explanations, that make sense. I bought TAC for my 77gr loads but decided to try it on 55gr since it's listed on the recipe. Now I know the consequences...