help me debug my AR loads

[Texas Boy]

I'm starting to load some ss109 projectiles for my AR. The projectiles have a canalure, so I initially tried seating the bullets to the middle of the canalure. This resulted in an OAL of about 2.250" - or 0.010" under max. (note: cases trimmed to 1.755". Since this brass was only fired once, some cases only measure 1.745"). A light crimp was then applied using a Lee factory crimp die.

While cycling these cases through my AR (M4 feed ramps, FWIW), 2 out of 10 caught a tip on the way in and stopped the bolt. The jammed rounds looked pretty chewed up - but when I ran them through a 2nd time they fed no problem. I then made 10 new rounds with an OAL of 2.240" and experienced the same problem. Again, the bad rounds fed fine when run a 2nd time. In fact, I ran the bad rounds repeatedly with no issues (after the first failure).

I then created a single round with an OAL of 2.230". The round feed fine, but I did notice some light scrape marks on the projectile. Does this mean the round still is not feeding perfectly?

For reference, I measured the OAL of 2 different types of 223 ammunition I have on hand - both have functioned reliably in this AR. One had an OAL of 2.250", the other was 2.220". The 2.250" rounds were Q3131A Winchester, and the 2.220" rounds were 62gr American Eagle (Federal).

I'm assuming the contour of the projectile has some bearing on the best OAL for a self loading rifle. Is OAL the source of my problem or is something else at work here? How deep can I set the ss109 projectiles? At 2.230" the canalure is barely visible - which I assume is about where it should be. I could probably go 2.220", but any further would place the canalure too deep.

Thanks!

[joelogic]

Just to be sure. Does your gun shoot factory ammo fine? And does the receiver have M4 ramps?

[Texas Boy]

Hey Joe,

Yes, the upper receiver has M4 ramps, and the factory ammo (Q3131A and American Eagle mentioned above) shoot fine. In fact I've never had a failure to feed (or extract) with this gun.

BTW - the loads hanging up appear to be jamming partly in the chamber - the bolt is about midway through the mag or slightly further when it jams.

[domokun]

Here's the SAMMI specs for .223:

[ar15barrels]

Yes, the upper receiver has M4 ramps, and the factory ammo (Q3131A and American Eagle mentioned above) shoot fine. In fact I've never had a failure to feed (or extract) with this gun.

Well there you go.
You don't actually HAVE a problem then.
Don't test feeding on the bench and expect the results to be the same as live fire.
The buffer bounces off the rear of the buffer tube and sends the bolt forward with more force than you get by simply releasing the bolt from the bolt catch.

It's also normal for bullets to get scratched during feeding.

[Texas Boy]

Thanks Randall. Makes sense. I spoke with a buddy of mine who has reloaded for ~30 years and he agreed. I also took 2 magazines of factory ammo and ran them through in the same fashion. Only had 1 failure - not nearly the fault rate I saw with my own loads, but it was a fault - which proves your point.

Thanks,
Mark

[joelogic]

I believe Randell's point was there is nothing wrong with your gun. But you are still have failures. What kind of failure? Is your gun properly maintained? I hate to ask but lots of people dont lube their guns and then wonder why they dont run.

[ar15barrels]

I believe Randell's point was there is nothing wrong with your gun. But you are still have failures. What kind of failure? Is your gun properly maintained? I hate to ask but lots of people dont lube their guns and then wonder why they dont run.

He's having problems with cycling rounds at home, without actually firing.
Of course, testing for feeding without actually firing is sorta like trying to check if your engine is going to overheat without actually starting the engine...

[Ninja45]

I agree 100% with what AR15 said!

[Bug Splat]

I agree 100% with what AR15 said!

+2

My AR sometimes hangs on rounds if I hand cycle. Firing shows zero problems.

I set my COL to what every LC M855 is (don't recall, die has been set that way for years). Never had a problem.

[Texas Boy]

Success!!!!

Yes Success!!!! We have a winner!

Took my very first reloads to the range today. 60 rounds of 223 with 6 different loads....All 62gr ss109 projectiles, TAC powder. Federal brass. The loads were:

22.0 gr, 2.2250"
22.0 gr, 2.2240"
22.0 gr, 2.2230"
22.5 gr, 2.2240"
23.0 gr, 2.2240"
23.5 gr, 2.2240"

I started by shooting 10 rounds of Federal 62gr factory loads, then 10 each of the above loads, followed by 10 more factory to make sure my shooting wasn't going to pot. All were shot at 50 yards, prone.

First off - All the rounds fed, fired, and extracted fine. My gun didn't blow up, nothing bad happened, no squibs or wild rounds. This alone was enough to make me very happy.

But even better - the factory groups were about 2" or slightly more, where as my best hand loads (the first group above) were only 1" - half the size of the factory loads. Now I know 2MOA isn't anything to throw a party over, but this was through a chromed 16" barrel (1:7 twist), using a red dot sight, and I'm not exactly a national match champion.

Less than half the cost and twice the precision of factory - not bad!

The ss109 round has a steel core - making it longer than a normal 62gr round. They were considerably less expensive than other 62gr or heavier bullets I could find - so I decided to give them a try. However, while I have load data for 62gr lead jacketed projectiles, I wasn't sure how this would translate to the ss109. From my limited data I can see there is little difference in group size between 22.0gr and 22.5gr of powder. The 23.0 gr loads are slightly worse, and the 23.5 gr loads are almost as spread out as the factory loads.

Now granted, without shooting multiple groups I can't be sure it wasn't just me not doing my part, but that's OK for now. I know 22.0 gr and 2.2250" OAL will shoot tight and feed fine - plus it uses less powder! I'm only using it for tactical competition - so I could care less about max velocity, and range will be 50 yards or less most of the time.

It has been several months since I started down this reloading path (most of that was waiting for my dies!), but the Calguns community has been a great help. Thanks to everyone who answered my questions or posted reloading information on Calguns. And special thanks to Randall (AR15Barrels.com) - not only has he answered several of my reloading questions and created some great tutorials, but he sold me the barrel on my gun. Now perhaps with all the inexpensive ammo I'm making I'll learn to shoot it worth a darn.

Cheers,
Mark

[ar15barrels]

Less than half the cost and twice the precision of factory - not bad!

Bah, reloading is not worh it by the time you factor in your time...