New caster/reloaded needing verification

[TexasAggie06]

"Never half-*** two things, whole-*** one thing"

-Ron Swanson

That can pretty well describe my mentality when it comes to projects and hobbies, so when the wife gave me permission and a reasonable budget to renovate my shop and invest in reloading gear I didn't waste any time and went to work. Within a month I went from having shed that could have doubled as a Halloween fright house, to having a legit shop with brand new casting/reloading gear. I also went from having a generally vague idea of what reloading was to, in my opinion, having just enough knowledge and experience to be dangerous.

So far I've cast, powder coated, loaded, and shot 500 rounds of .45 ACP with good success. All 500 rounds went down range safely and only two pieces of brass failed to eject properly, I'm not sure how you would rate that for a newbie, but I'll take those numbers. Now here comes the dangerous part...

I realize as a new reloader that the likelihood of making a dangerous error is now, I am finally ready to take my AR-15 along with first batch of 300 Blackout to the range and I'm honestly a little nervous. The lack of published data specific to what I'm about to send down range is what has me on edge. That being the case I would greatly appreciate your review of my process and verify that the ammunition I've loaded is safe.

Gun data:
CMMG RCE .300 BLK
18" Stainless medium taper barrel
1:7 twist

Boolit data:
Lee mold C312-155
sized and Gas Checked to .308 with Lee push thru die
Powdercoated with HF matte black
sized to .311 after PC
all boolits QC'd and weighed in between 154-156 grains

Brass data:
cleaned, trimmed, and prepd
CCI small rifle primer

Load data:
5 rounds each for testing
IMR 4227 powder
14, 14.5, 15, 15.5, and 16 grains
bullets seated to the top crimp grove giving them a COL of about 2.03"
lightly crimped

my major concern is seating depth and whether or not I've got those suckers stuffed in there too deep combined with too little/much powder.

[TexasAggie06]

[jcren]

Sounds good to me, I don't use that powder but reload my brother in law's 300 with that bullet and accurate 9 for great pointers that will cycle.

[cajun shooter]

Actually, Now is not the time that most reloaders have that Oh .... moment, it's later on when you feel that you have it all down pat. Welcome to the fold my friend, David

[Pee Wee]

Texasaggie:
I would recommend that you take an NRA certified reloading course, also Duke in Florida is a great source to get good reliable info from. He is a certified NRA RELOADING INSTRUCTOR. I took his course and found it invaluable. He may know of an instructor in your area.

[Harter66]

The 300 isn't my cart . The data looks right. That 1-7 is kind of steep for a light bullet but with the small case you should be good to go .

Something that I just ran into was that a start load failed to pickup round in a 6.8 AR. The next load ran as intended but didn't fully engage the bolt hold open ,enough to hold but not fully. The next load only caught the magazine follower . I stopped there in spite of having 3 more .5 gr steps . The consensus is that I hit a plateau where the bolt was trying to extract a case still pressurized to the walls . This may change later as the rifle has just 60 rounds through it now and the 1st 10 of 18 factory rounds were just ugly as if they had been an a sand blaster.
Just something to be aware of should it come up.

[bedbugbilly]

Welcome!

And cajun shooter speaks wise words! Doesn't matter how "new" or "old" you are . . . you need to pay attention and on our toes!

Good luck and have fun!

[Seeker]

Actually, Now is not the time that most reloaders have that Oh .... moment, it's later on when you feel that you have it all down pat. Welcome to the fold my friend, David

My thoughts exactly. Sounds like your doing alright. It's when you think you got it mastered and are really good at it is when you can get into trouble.

[TexasAggie06]

Much to my surprise the ammo worked flawlessly, 15.5 grains resulted in some nice groups although the accuracy wasn't as consistent as factory fmj. I guess that gives me something else to obsess about.

[Green Monster]

I run that same boolit in my 300. I use h110 as my powder and have no issues with it. Ive also heard 1680 is good as well. Your loads look ok to me. Any reason why you size then pc then resize? Ive just pcd then sized and loaded. Im just starting out with pc boolits so i might be missing something.

[John Wayne]

You're off to a great start. If there are any doubts in your mind follow my buddy Pee Wee's suggestion.

[Teddy (punchie)]

I always use to sources for data. Type-O's can happen. Some custom shops like the loads hot. Learn to look at cases (brass) they will tell you a lot. Primer and primer area, is the best place.

Hornady data has 150-155 grs. bullets jacketed at

12. 9 grains of IMR 4227 @ 1500 FPS,

and max at 16.3 grs. of 4227 @ 1800 FPS

Loads sound good.

Keep a loading log. (sp) Write it all down. Never listen to any load by mouth with out checking with someone else at least or finding data in a manual.

Be Safe have Fun !! Teddy

[Moonie]

And NEVER reload from memory, no matter how long you have been loading that load. ALWAYS verify the load. And keep good notes of what works and how well it works.

[popper]

I use on-line Hornady data, stay away from max load to begin. I don't use that mould so no info for COL, just don't jam the lands and make sure converted brass all fits. My 144gr PB goes 1750 over 15.5 4227, HiTek or PCd. Hard to keep ammo loaded for this beast.