300BlkTalk

Is there a formula for determining the RPM a bullet is traveling using velocity and twist?

Thick necks need to be turned, not reamed.
Stick with the brass on the good brass list in the stickie.

Good argument for rolling your own.

Magpul makes a mag for the 300BO. The only difference is the rib in the standard 5.56 mags is thicker.
The thicker rib causes the bullet to sit incorrectly, but I think that only applies to the heavier bullets used for subsonic.

A lot of it is a carry over from the romanticism of the Old West. Some is just brand recognition. Colt has produce some excellent firearms over the years, but they still maintain the reputation of the world's largest manufacturer of unfinished firearms.

Some lubes may be better than others, but about any f them, properly used, should work. I've used Dillon lube for everything up to .308.

Dr.: Do you keep firearms at home?
Me: How much liquor do you keep at home?
Dr.: That isn't relevant to your exam.
Me: Neither was your question.
Conversation Over..

Check neck thickness. .014" or thicker will be a problem.
Compare the head stamp(s) with the list in the stickie in the reloading thread.

How about some relative information on your reloads. You are not shooting 230gr bullets in a 5.56 case.
Start with what caliber. You never answered that.

Do the primers look like they’re seated properly? If primers aren’t fully seated the result can be FTF. Are there good dimples on the primers? Are you able to measure the case? it’s not unusual for cases to be undersized as a result are too short and case head is not reasonably tight against the bo...