Barrel Drop Test ?

T

tjlis2004

Inactive
Good afternoon all,

I'll start of by saying this is my first post here and I'm new to reloading so please forgive any wrong terminology used.

I'm reloading 9mm 124 gn rn ACME bullets using a Lee Load-Master. I have created a bunch of dummy rounds to test in the barrel of my gun. I'm using a 4" SA XD MOD 2. I've figured out that my OAL length to where the round spins freely and falls out without any issue while remaining flush with the bore is 1.060. What I'm wondering about is deviation in rounds. Out of the few rounds I've done I have a couple that are higher then the OAL and slightly hang up or won't fall free. They measure 1.070, 1.075 and I have one that measures in at 1.080. Being that this isn't every round is it safe for these deviations to be fired or should they be set aside? What would be considered a safe deviation in cartridges?

Thank you in advance for any guidance given.
 
I've run into this issue with 9mm before.

When it happened to me (some handloads being a bit too long, but they would still chamber in my pistol), I just shot them. Accuracy wasn't great, but that was the only problem I had. I need to add the caveat that, while that worked for me, I can't guarantee it will work for you. I was shooting a Glock with an after-market barrel that fully supported the case.

I assume you're probably loading mixed head stamp cases, and that's probably why you're getting the differing OAL's. When I had the same issue, I pulled out one of each brand of case I was loading, determined which one had the longest OAL, and set my dies based on that brand.

That means in other cases I'm going to have shorter OAL's, but I'm loading only mid-level powder charges so I'm not worried about a range of 0.02 or so.
 
Pistol bullets can have quite a bit of seating variation but it sounds like you're loading plated bullets with a flat seating stem? Try lowering your average seating depth 10 or 20 thou.

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Thank you Tennessee Jed for the informative response. I am running mixed head stamps and never thought of the mixed head stamps causing the issue.

I plan on running mid powder charge for these reloads as they will be for plinking purposes only.
 
TJB101

I will be using Titegroup. I have not loaded any ammo to take to the range yet. I plan on testing 3.5 gn and 3.8 gn of powder. I'm using lead polycoated bullets that are 124 gn. The only lead load data I found says 3.2 to 4.1 for load data.

The Load-Master's disk lowest setting is 3.5 gn of powder. The next size up is 3.8 so I'm limited in the refinement that I'm allowed to make in the powder charge.
 
Nosler Guy

Thank you for the reply. I'm using 124 gn poly-coated lead bullets. The company I purchased them from is ACME bullet company and they do not state any reloading data on their site.
 
My experience is with jacketed bullets but I have never had problems with differences in over-all length when seating bullets into cases with different lengths.
The seating depth is set by the die and the position of the shell holder. How can you get differences in over-all cartridge length when the distance from the bullet to the head of the case is the same unless the bullet ogive varies enough to affect it?
 
If the cases are different lengths it can cause some variation on how hard you're actually crimping. If a case is longer than the rest the crimp will be a little tighter. It will take more pressure to seat and can deform the bullet slightly and cause length variation. I have similar issues with berrys plated bullets but I don't load them long enough to hang up in the chamber.

In a compressed rifle load you can run the handle down 5 times while seating the same cartridge and have 5 different bto lengths.


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I can't see how the case would effect the OAL. Variations in the nose shape of the bullet could effect how deep a bullet will seat.

The shellholder and bottom of the case will always be mated together. A 9mm case at .750 or .760 will produce the same OAL. Differing case lengths will screw up your crimp.

It's possible to short stroke the press and not get that last bit of travel.
 
I have my dies setup for maximum case length in the guns I shoot. My trimmer is set up for the shortest cartridge I reload and then I have bushings to cut the longer cases. I never have to reset my trimmer and that means that eventually all the brass grows to the same length as the others in the same caliber. The only cases I crimp are 38, 357 mag, 357 max,and 9mm. With them set for maximum length cases I never get over crimped cases. I do get some 38 special cases that are short because they don't get used much but all the others are just maintained at max.
 
It is the deviation in the bullet not the brass. A slight difference is length of the brass alone does not change the COAL.

Measure a batch of the bullets and see if the vary by much.

As mentioned just seat your seating depth a little deeper to offset for the variable bullet length.

If you have bullets that have a cannelure or crimp groove then the actual brass length will matter.
 
I measured the bullets and there is some variation. The highest was .02. I will set the seating die for the highest bullet length to overcome the different bullet lengths. Reading through the responses it sounds like I should be safe as long as I use a mid-level charge.

Thank you everyone for the ideas and guidance. It's great to have such a helpful community.
 
Take a look at HOW the steating stem contacts the bullet. And WHERE.

A steating stem for RN bullets has a hollow cavity for the tip of the bullet to enter, and does NOT press on the very tip, but on the circumference of the bullet NOSE, slightly behind the very tip.

With this kind of contact, you WILL get tiny variations in overall length, because even though the die is setting the seating depth uniformly, the bullets themselves have small differences in length.

If you measure from the case base to the point the seating stem contacts the bullet, I'll bet you'll find it to be pretty uniform.

Now, if you are seating a flat nose bullet and using the proper SWC seating stem, the stem is contacting the flat TIP of the bullet with the corresponding flat spot of the seating stem, and you should not see any variation in overall length, due to different lengths of individual bullets.

Personally, I think you are being a bit OCD over 0.01" or so in a pistol round.

Now, if you were loading for a benchrest rifle, OCD is the name of that game.
:D
 
"...plan on testing..." Don't pick a load and hope. You need to work up the load from the start load to the max load. Load 5 of each and go up by(in this case) .1 of a grain. Use the Max OAL for 9mm(1.169"). Save you a lot of mucking around. And that's from the point to the flat of the case head. No ogives.
If you're getting erratic OAL's it usually means you're not operating the ram the same way every time. Doesn't take much to throw the OAL off a tick. Take some time to get it right.
Those 1.070 etc are very likely sticking into the rifling. You can try just reseating, but you'll probably have to pull 'em depending on how hard the crimp is.
"...The highest was .02..." That's 20 thou too long. Also means the weights aren't the same. Isn't a safety issue though. Just a feeding/bullet seating issue. Won't cause any damage. Lots of irritation though.
 
44 AMP Thank you for the post. You're probably right about me being a little OCD. It happens lol. I'm looking at better safe then sorry but after reading a few of the post here it looks like I'm the crazy guy in the bubble haha.

Great info. Thank you!
 
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T. O'Heir I definitely plan on testing with smaller loads. I built dummy rounds to test OAL before even putting powder in. It's good to know .020 won't cause major issues but will be frustrating at best.
 
After all the advice I loaded up some live rounds and finally got to the range. Here is an update.

I shot two batches of 5 bullets each.

First Batch
Case: Range Brass
Bullet: ACME 124 gr RN poly-coated lead
Primer: CCI 500
Powder: 3.4 gr Titegroup
OAL: 1.060 + or - .01

Second Batch
Case: Range Brass
Bullet: ACME 124 gr RN poly-coated lead
Primer: CCI 500
Powder: 3.8 gr Titegroup
OAL: 1.060 + or - .01

I'm happy to say that everything went without a hitch!

The 3.4 gr load didn't have much recoil at all and felt kind of weird when being fired. It's accuracy wasn't very good and the group was large with this low powder charge.

The 3.8 gr load had more recoil but felt better when fired. The accuracy was much better with a nice group. This will be the load I use.

Thank you everyone for the tips and advice. I'm happy to say that I'm now a proud member of the reloading community.
 
To point out an oddity, I loaded for my hi power. I loaded a ton of jackets that seemed to work in testing, but did not function reliably in real life. I used another loAd, thousands, and they didn't function reliably in my glock, even though the passed plunk tests as well.

Tiny deviations in chamber, bore, leades, when I loaded these rounds to fit tightly and reliably, those almost immeasurable differences blocked them. At the end of the cycle, a lot of forward pressure is lost as the thing cams upward.
 
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