Strange accuracy degradation after I started using SDB - 9mm

[MilkMyDuds]

I have been loading 9mm for a few months. Started off with RCBS single stage and Lee 4-die set. Ran flawlessly except it was extremely slow. With more live fire practices, I realize I need a progressive press.

So I bought an SDB from Brian's store. Great little machine. I have since loaded about 1000 rounds.

The problem, however, is that I started noticing dramatic accuracy degradation with these rounds loaded off SDB. In my match, I kept missing 10 yard steel for 5-6 times while standing still doing 1 shot per second, while previously in both matches or practices I could easily hit them on first attempt with 0.3 or 0.4 split while moving. There are many other strange accuracy issues that I won't list here.

I tested the gun with my previous single stage loads, and although they were not great, they are acceptable, <3 inch or so at 15 yards and <6 inch at 25 yards. I have not change my recipe - it has always been Berry's 147gr plated + 3.1gr Titegroup and OAL=1.148

Finally I bought some Winchester 147gr, Federal 124gr and Remington 115gr ammo for some serious testing. I shot with and without sandbag rest at 15 and 25 yard distance. Each group is 10 rounds.

I can quickly tell that the handload is performing horribly compared to the Win 147gr commercial. For example, 10 rounds at 15 yards distance no rest, SDB handloads at 4+ inch group while the Win 147gr only 2.7 inch (<2 inch if I exclude the flyers).

The other very obvious issue with the SDB loads is they fly upper left corner, while all the factory ammo are pretty centered.

I did not take 25 yards pictures but my conclusion is that somehow my recipe with SDB is not yielding acceptable accuracy, compared to my previous handloads. Is this possible?

I have gone through a list of possibilities:

1. Human error? - No, same shooter and can shoot well with factory ammo

2. Gun problem? - The gun is 4 months old and has only 6000 rounds through it. Just in case, I went ahead and ordered an KKM barrel. I will test again when the barrel arrives.

3. Over crimp with SDB? - I measured case mouth and base, they are 0.377'' and 0.390'' and seem perfect

4. Berry's plated does not work with SDB? - Is this possible that SDB seating die cannot consistently seat the plated bullets? This is the most viable theory currently, because the Win 147gr factory ammo is FMJ.

Does anyone else load plated 9mm with SDB notice any accuracy issues?

Please do help a very desperate shooter. Thanks.

[yoshidaex]

Just throwing it out there but possibly a Berry's batch issue?

How about trying different crimps i.e. 0.375 to very little crimp?

[Bkreutz]

I used to have problem with Berry bullets, now I use either Xtreme or Rocky Mountain, I crimp them to .375.

[MilkMyDuds]

I have some Xtreme on the way. I will test them out.

0.375 is more crimp than 0.377 (what I have right now), right? So I should keep my SDB as it is then.

[Hi-Power Jack]

1. I noticed accuracy degradation with SDB. In my match, I kept missing 10 yard steel

2. my previous loads, are acceptable, <3 inch or so at 15 yards and <6 inch at 25 yards.

3. handload is performing horribly compared to the Win 147gr commercial.

4. 15 yards no rest, SDB at 4+ inch group while the Win 147gr only 2.7 inch

1. Unfortunately, missing 10 yard steel has no correlation to the accuracy

of our handgun/ammo combination (don't ask how I know). To measure

accuracy, only shooting slowly at paper targets can tell the difference

between a 2" and a 3" group.

2. Not sure I'd accept 3" groups at 15 yards or 6" at 25 as acceptable, but

that's okay for a 12 - 15 shot group offhand.

3. I'd test the 2 rounds at 15-20 yards, with a rest.

4. each gun has preferences - your gun might prefer the WW 147 grain

over the Berry's plated bullet (I would venture to guess that MOST

guns would also prefer the WW 147 gr).

As I mentioned in another posting on the same topic that you did a few

days ago - I would suggest testing other bullets. Not sure your gun

really enjoys the Berry's. I know you bought a ton of them, but you

owe it to yourself to test some other bullets to see where the problem

lies.

And, there is no way that SDB is causing the problem - I've been using

two SDB's for 20 years, and have loaded close to 50,000 rounds of

9mm minor and major ammo - my TruBor, using SDB loaded 9mm

major, will group at 2" at 25 yards, if my 70 year old eyes do their part.

Possible that it could be a glitch in the crimp, OAL or powder charge

that could be causing some of the loss of accuracy - I'd try a few

different OAL's, check the crimp by pulling a couple bullets and looking

for a ring around the bullet, and try a little more or less powder.

But, I'd definitely try some different weight and brand bullets, as well.

BUT, it CAN'T be the SDB - believe me.

Good luck with it - hope that helps a bit.

p.s. did your bullseye shooting buddy ever fire any of these rounds,

or look at your reloads?

[trgt]

Some things you can do to help reduce variance on testing

- sort brass to a single headstamp to load for a batch (i.e. Federal, Blazer, etc)

- don't include rounds in the test that were loaded when shell plate not full (only test rounds where all stations were full when loaded)

- do 10 powder drops into shells on the SDB (weigh each), and ten as you do on the single stage and compare to see if weight and variance similar

As mentioned above, try with as little crimp as possible, and several different settings

last, don't a/b compare to factory, they have nice clean single headstamp brass and uniform loading compared to most folks when they start. You should do a/b comparison with all same components, do a quick run on each setup, so you can see results now, that will rule out something that has mechanically changed in the gun since you last remember testing.

Hope something there helps. BTW, Berry's 147 and 124 very accurate for me in a CZ when I used it.

Edited December 2, 2014 by trgt

[pjames32]

I load 45ACP & 40 S&W mostly. About 75% cast lead and 25% jacketed. I've loaded Berry's and not seen a problem. The same with Accurate. I'd do some paper shooting from a rest if you need it.

The suggestions on taper crimp are good. You might try to vary it.

Good luck.

My 2 SDB's have been great. Purchased the first one in 1992.

PJ

[NoSteel]

Can you pull a bullet and post a pic showing if there is a crimp line?? I'm on the side of crimp issue with Berry's....

[TightLines]

I once had accuracy issues with Berry's 115 gr bullets. It was suggested to me that they could be undersized. I took the calipers to them and found many at .353" instead of .356". I'm not sure if that's enough to make a difference accuracy wise but I moved away from Berry's and haven't had a problem since. Switched to Xtreme and have no intention of going back.

Edited December 2, 2014 by TightLines

[MilkMyDuds]

1. I noticed accuracy degradation with SDB. In my match, I kept missing 10 yard steel

2. my previous loads, are acceptable, <3 inch or so at 15 yards and <6 inch at 25 yards.

3. handload is performing horribly compared to the Win 147gr commercial.

4. 15 yards no rest, SDB at 4+ inch group while the Win 147gr only 2.7 inch

1. Unfortunately, missing 10 yard steel has no correlation to the accuracy

of our handgun/ammo combination (don't ask how I know). To measure

accuracy, only shooting slowly at paper targets can tell the difference

between a 2" and a 3" group.

2. Not sure I'd accept 3" groups at 15 yards or 6" at 25 as acceptable, but

that's okay for a 12 - 15 shot group offhand.

3. I'd test the 2 rounds at 15-20 yards, with a rest.

4. each gun has preferences - your gun might prefer the WW 147 grain

over the Berry's plated bullet (I would venture to guess that MOST

guns would also prefer the WW 147 gr).

As I mentioned in another posting on the same topic that you did a few

days ago - I would suggest testing other bullets. Not sure your gun

really enjoys the Berry's. I know you bought a ton of them, but you

owe it to yourself to test some other bullets to see where the problem

lies.

And, there is no way that SDB is causing the problem - I've been using

two SDB's for 20 years, and have loaded close to 50,000 rounds of

9mm minor and major ammo - my TruBor, using SDB loaded 9mm

major, will group at 2" at 25 yards, if my 70 year old eyes do their part.

Possible that it could be a glitch in the crimp, OAL or powder charge

that could be causing some of the loss of accuracy - I'd try a few

different OAL's, check the crimp by pulling a couple bullets and looking

for a ring around the bullet, and try a little more or less powder.

But, I'd definitely try some different weight and brand bullets, as well.

BUT, it CAN'T be the SDB - believe me.

Good luck with it - hope that helps a bit.

p.s. did your bullseye shooting buddy ever fire any of these rounds,

or look at your reloads?

Thank you Jack, for the great insights.

As you suggested, I pulled a couple rounds. Here is the pic for one of them. They both look like this.

BTW - the case mouth measured 0.379'', and base 0.390''. I do not think they are over crimped.

I have not got a chance to have my friend shoot my handloads yet. I will do that this weekend hopefully. For now, I will try to compare with no crimp at all, see if it improves.

[DougCarden]

The bullet has been squeezed pretty good. Try belling your case mouth more and crimping to .378 and see if the bullet looks like that when pulling it.....

DougC

[MilkMyDuds]

The bullet has been squeezed pretty good. Try belling your case mouth more and crimping to .378 and see if the bullet looks like that when pulling it.....

DougC

I did not adjust belling of the case mouth, but I simply turned the crimping die out a couple turns, now there is no line at all:

[MilkMyDuds]

I guess what I learned from this experience is that, even though the measuring of the case mouth and base seem to be in line with spec, it can still over crimp...

I suppose that line on the bullets is causing potential accuracy issues.

Now I will try the new batch without the crimp line and see how they fare. Thanks everyone for contributing and helping me out!

[DougCarden]

Try this. Add enough crimp so there is no rough edge on the case mouth, then drop test it in your barrel. If it will drop in and out smoothly then make some of them and test them. We get hung up on numbers but that is all you really need.....

DougC

[MilkMyDuds]

I am a bit confused... so the line on the bullet due to crimping is bad or good? Sounds like you want there to be a vague line but not too hard? Will my current crimping be fine for accuracy? All of them are passing a chamber gauge. These should be good for accuracy, right?

[BritinUSA]

There should be no line on the bullet.

[Hi-Power Jack]

No reason to have a line on the bullet.

Not really "crimping" 9mm ... just removing the

belling we did to allow the bullet to get started

seating.

[Powder Finger]

what Doug said plus........

seat a bullet and crimp just enough to leave some bell. Then put calipers behind the bell and lock them. Now just keep adjusting the crimp until you can just slide the calipers off the case toward the front. This is where you want to be. no real crimp with no bell.

[dauntedfuture]

There are many other options out there other then Berry bullets; I would go with another bullet. While your tests are not scientific I don't think the press has anything to do with your issues. Provided you are using all the same components and your dies are all set up to yield the same dimensions in both presses is that one press might have a little better run out then the other and one powder system will be more consistent then the other. I believe that when you set the SDB up you applied more crimp then you had before.

[benos]

what Doug said plus........

seat a bullet and crimp just enough to leave some bell. Then put calipers behind the bell and lock them. Now just keep adjusting the crimp until you can just slide the calipers off the case toward the front. This is where you want to be. no real crimp with no bell.

Perfect.

Think of the crimp die as really as "bell removing" die.