Adjusting my 9mm load for accuracy

[johnandersonoutdoors]

Hey everyone,

I have been into the reloading hobby for about a year now. I am basically loading 9mm exclusively, and I am using 115 grain FMJs from Montana Gold.

The first load I worked up was 1.135" oal with about 5.2 or 5.3 grains of Unique. I have been shooting that load a lot but recently decided it is not as accurate as I would like.

Then I tried 1.150", along with the same 5.3 grains of Unique, which seems to be doing a little better but these rounds still aren't as accurate as I would like. They are beating the 1.135 and they beat factory ammo for accuracy but not by much.

This weekend I am thinking about going in the opposite direction. I think I will lower the oal to 1.125" or maybe even a little shorter.

What do you guys think? What is the shortest I should attempt with this bullet? My powder charge is definitely at the low end already. Do I need to reduce the powder charge a bit as I go for shorter oal?

Thank you for any advice.

 

[warhwkbb]

Often, but not always, the most accurate load will be at a place where the powder burns most efficiently. Your combination is with a light (for caliber) bullet and medium burning powder. There will be an endless combination of powders, bullet weights and styles, combined with how the bullet is crimped if at all and of course COAL.

 

[ETXhiker]

As a quick suggestion, keep the Unique but try some 124 gr. MG or other brand hollow points. Longer bearing surface on the heavier bullet and HP's seem a little more accurate than FMJ's in most guns.

 

[johnandersonoutdoors]

I appreciate the feedback guys, but I am really looking to keep moving forward (for now at least) with the 115 grain Montana Gold FMJ.

Any input on how low I should go with oal?

 

[918v]

U should increase the powder charge.

 

[johnandersonoutdoors]

918v,

The charge feels about the same as 115 grain Winchester white box. It cycles the slide reliably so I have stuck with it. What do you think I should increase the charge to?

Any help on adjusting the oal as I try to find the most accurate 9mm load I can in my M&P 9?

 

[DaBruins]

When I'm working up a new load, I compare 2 or 3 manuals for starting load recommendations, which I use as my starting point. I'll load 10-15 rounds at the starting load, then I add .1 gr for the next 10-15, and so on, until I get close to the max load recommendations. Having 10-15 rounds of each recipe allows you to check for proper cycling, ejection pattern, unburned powder/residue, etc. I then put out a target for each recipe and shoot from a rest to check for accuracy. When I find a load that fits the bill, I'll save the target (along with the load data written on the target) in a binder for future reference. It may sound tedious, but for me it's more relaxing than meditation!

 

[DaBruins]

BTW, I've had great success with AA #2 for 9mm. I use it for both 115 gr and 147 gr fmj. Here's my "load work-up" target for the 147 gr round I use in my Kimber, which has a 3" barrel, shooting at 30' (ignore the miss at 12 o'clock- operator error!)

 

[johnandersonoutdoors]

DaBruins,

That is pretty much what I have been doing. Went to the range today with a new recipe. I put my target about 30 feet from the muzzle of my M&P 9. Sat down at the bench and rested my hands/gun on a bench rest bag. I put 20 rounds in each target. Other than one or two outliers, I can cover the bulk of the hits with a closed fist.

What do you think of this accuracy? What do you guys strive for from your semi auto pistol handloads?

 

[johnandersonoutdoors]

Haha....looks like we were typing at the same time. Now I see your target.

Ok, so you are doing a lot better than me in terms of accuracy. What type of rest do you use?

 

[1SOW]

When I'm working up a new load, I compare 2 or 3 manuals for starting load recommendations, which I use as my starting point. I'll load 10-15 rounds at the starting load, then I add .1 gr for the next 10-15, and so on,

I use a similar method. I load 5-10 in small powder increments. I shoot them across a chrono at targets for each different load. The groups will be better for one or two of the loads.
If the performance at this oal is good, I load maybe 20 each of the better loads and repeat the test, including off-hand for a 'feel' test final exam.

If it doesn't meet my goals, a different bullet or powder may be needed, and start again.

Just a comment: With 9mm pistol, I find that the best accuracy and chrono numbers ARE NOT NECESSARILY the best for off-hand accuracy with fast follow-up shots..
Voodoo, magic and juju also matter.

 

[DaBruins]

What type of rest do you use?

Nothing special. It's two pieces of plywood nailed together to form a "T" and a piece of recycled carpet tacked to the vertical piece. It supports the barrel, and my hands support the grip.

 

[DaBruins]

And to answer your original question regarding OAL, I also load to 1.130" for my 115gr fmj. You might want to do a little more research on using Unique in 9mm- from what I'm seeing 5.2/5.3 is on the low end of the charge range. Check the Alliant web site, or try emailing their tech support for recommendations on your particular bullet/powder combination.

 

[918v]

918v,

The charge feels about the same as 115 grain Winchester white box. It cycles the slide reliably so I have stuck with it. What do you think I should increase the charge to?

5.5, 5.7, 5.9, etc. until you hit your accuracy or max pressure.

 

[918v]

Any help on adjusting the oal as I try to find the most accurate 9mm load I can in my M&P 9?

OAL is one of several variables. I play with OAL at every charge weight. You may find, though, your pistol is incapable of good accuracy with that bullet/powder combo.