124 RN Precision Deltas in SR9 problem

[War]

I bought 2000 Precision Delta 124gn RN FMJ, so far I've tried working up loads over HS-6 and Power Pistol. I'm not sure what I'm doing wrong, but I can't seem to get better than a 8in group at 15yards with these things (I'm not a great shot, but I'm not that bad). I'm using Hornadys 8th edition book for the data, making batches 0.1gn increments from min to max with [email protected]. I'm thinking it might be the OAL, or taper crimp might have have been tightened down somehow (if so, not visibly excessive). Anyone else run these bullets in an SR9 @1.150 with issues? I've already wasted 250+ rounds worth of supplies and time on this, figured it's time to ask questions.

Few things to note: Used the same data for developing good loads with Berrys Bullets and Rainiers.
The bullets themselves seem fairly consistent in weight, diameter and length. I find a few odd ones here or there, but no more than any other brand I've tried.
Brass is FC, some of it reloaded multiple times.
I'm still pretty new to reloading, so I might be missing the elephant in the room.

 

[dougader]

I'm assuming you have fired other loads through the SR9 that gave acceptable accuracy?

I don't think I've ever loaded 9mm to 1.150 but I see my Hornady 6th Edition lists that length. I usually load my fmj's to about 1.130.

I would pay attention to how much taper crimp you are applying to your loads, too. You're basically just taking out the flare to make the case straight again. Just a slight crimp should do it.

I haven't used Power Pistol, but I know with HS-6 I got better accuracy - and burn - with near max loads. For lighter loads I suggest a faster burning pistol powder.

Don't think of your experience as wasted supplies. You always learn something along the way.

 

[44shootist]

Just barly use enough crimp so the bullets don't back into the shells from recoil, some people don't crimp bullets at all for semi auto's.

Could be the bullets them self don't work well for your gun should have just bought 100 to try them.

All bullets, brands, types, and weights will all shot different in different guns, you need to find the bullet that works best for your gun before you buy 2000 of them, also try different powders the see which one works best it can be an issue as well.

 

[Tam 212]

Shot in the dark but how are the groupings? All over or stringing vertically/horizontally?

In addition to crimp amount and consistency, primer seating depth also seems to be important.

I was getting some crazy vertical stringing at 15 yards and didn't know why until a more experienced reloader took a look at my reloads and commented on how I should make sure the primers are seated more consistently. Since then, from a rest position, 4" groups at 15 yards are now routine. Now if I can only do that as easily offhand......

I use a Rainier 115 gr. plated round nose with 1.145" COL with a light taper crimp. I don't chamber my reloads more than once or twice and they dont' suffer from any notable setback after being tested by chambering a dummy round 3 times.

I also use Power Pistol and it seems this powder seems to work better in intermediate or near full power loads. Clean and consistent but my complaint for this powder is in how flashy it is (I primarily shoot indoors at both my regular ranges are fairly low lit).

Good luck and hope you get the results you seek!

 

[War]

It turns out, these bullets aren't anywhere near as consistent as I thought. I had pulled a sample of 20 from each batch, weighed and measured. Those bullets seemed pretty consistent at around .355 dia and .596 length, but last night I started making a few more development batches, and I measured everything as I went. Bullet length was from .588-.600 and diameter from .355-.357 of 150 measured, who knows what seating depth I had used on previous runs, depending on how long the bullets were during setup. My seating die contacts closer to the ogive than the tip, but even that seems to be a bit off. I'm not sure how to measure the ogive accurately.

Anyone know what the likely consequences are of shooting a .357 fmj bullet in a 9mm?

 

[Tam 212]

Yikes. That is not very Precision.

More experienced reloaders might be able to provide more detailed answer but I would guess shooting a larger than spec diameter bullet will likely cause increased pressure and not be beneficial to accuracy. The bullet must be getting swaged slightly as it is fired down the barrel.

Of note is that some cheaper calipers have a variation of two-thousandths (±.002)... That bullet length variation is significant though.

 

[WESHOOT2]

No harm will come from a .357" bullet.

 

[Tam 212]

Really? I thought it was not advised to use .38 Spl./357M (.357") bullets in the .355" 9mm barrel?

 

[WESHOOT2]

I have "9mm" bullets that ten-thou mike from .354" up to .3575".
My "common" preferred "9mm" bullet diameter is .356".

I have tried bullets at .3595" (a 158g LRN for 38 Special; 9x19 gun had a 'generous' bore but its chamber was a bit too tight to fully chamber that fatty).

I have done my due diligence about fat bullets vs bore, and based on specifics, shooting fatties does no harm; no danger; no big deal.


And think about that .3595" bullet being pushed down my numerous 38/357 guns.....accurately, I should add.

 

[WESHOOT2]

I should add that even though I had to kinda (ha!) hammer those fatties into the chamber, they shot well.
I mean, since I'd made them, I had to test them.
I, of course, prefer a rd that chambers a bit more reliably.
Ay?