Where I'm at part 3; The Fast Burners

[RDub01]

Hello
Well got inspired to do another little 10mm research project. This time looking into the fast burners with 180gr jacketed bullets.

After doing some pull-downs with some of the 10mm factory loads,

http://www.handgunforum.net/range-report/31847-new-glock-20sf-armscor-180gr-fmj-report.html

http://www.handgunforum.net/range-report/32000-glock-20sf-american-eagle-180grfmj-report.html

http://www.handgunforum.net/range-report/32440-10mm-remington-umc-180gr-fmj-report.html

Commonly referred to as 'FBI Loads', the question came up.. Could I duplicate these loads charge = velocity.. Or put another way.. Is there a powder I have on the shelf that I could put, say 7.0grs in a case, top it off with a 180gr bullet, and get 1089 fps?.. Thus duplicating the REM-UMC load.

So I gathered some loading data for the powders I'm going to try, and went out to the bench and started loading rounds to find out.

A while back I scored some pulled Federal 180gr FMJ bullets from American Reloading, so this would be a good way to use the rest of those up.  Once fired Starline brass, treated with the Redding GRX die, was used throughout.

The first range session was a very warm day; in the 80°'s so there is no excuse for everybody to perform at their best.  Five round groups were shot from a Caldwell Pistol Rest at 25 yards.
Chronograph data was taken with an Oehler Model 33. Skyscreens centered 10' from the muzzle.
Gun is a stock G20-SF Gen3.

The last group shot (target #18) was the REM-UMC factory load.  It's worth noting that after shooting all those groups, I noticed the recoil of the REM-UMC load was noticeably sharper from all the rest.





Well Unique and Herco came through again. Even though Unique produced some of the worst standard deviations, it still shot some of the best groups. And some of the best SD's shot the worst groups.. Unique seems to do well in just about anything it is suitable in..
Titegroup did pretty well, but the best group of the day was 9.0grs AA #5.  231 might have produced a good group as well, save the 'flyer'..  Going to call that an error on my part for now.

According to case expansion measurements, the only load that was approaching the .4340" mark was 9.0grs AA #5. None of the other loads were particularly warm.
I was most curious about the data for AA#2.  Newer data indicated a max charge of 6.4grs, but older data indicated 7.4grs.  Well, it was obvious here that 6.4grs was not even close to a max charge.  Unique could go up another notch also.

So with the fifteen remaining bullets I loaded up some more rounds with Unique, AA #2 and at the last minute decided to include 7.6grs of CFE PISTOL.



Unique did about what I expected it to do.  7.3grs of AA #2 is definitely a max charge.. I wouldn't take it out any further.  The older data seems to be more realistic.
7.6grs of CFE PISTOL shot a bit faster with the WLP primer than the last time I shot this load with CCI 300 primers at 1054 fps. But, the temperature was cooler also at that time.

That evening I went into town to run some errands and actually scored some Winchester AUTOCOMP!  The store had about fifteen 1 lb. canisters. 
I have to include this powder in this exercise so I'll finish off with some Hornady 180gr HAP bullets.  I loaded up five rounds of 7.0 and 7.7grs of AUTOCOMP with the HAP bullet and WLP primers.  Just to make the exercise more complete, went ahead and loaded five rounds with 7.0grs of SR 7625 and CCI 300 primers and see what happens.





Well with the exception of one of those mystery flyers, SR7625 did pretty well..  Could take it up a tenth or two maybe.
AUTOCOMP delivered the highest velocity of all these tested.  7.7grs is definitely a max load.. No question about that.

That's all the powders I thought I should try for this.  I couldn't find any data for ZIP anywhere, but I would imagine it would behave much the same as 231, so I didn't try it.

So.. As to the original question;  Is there anything that duplicates the Armscor or REM-UMC load charge =velocity?..  No.  Some come close but no cigar..
So it seems the factories are using some pretty unique propellants to get that level of velocity with a relatively modest charge weight.

Here is the graph for this project and spread sheets;







9-17-17; I shot a group with 7.3grs of SR7625.  The data is reflected on new graph and spreadsheet.  And here is a target;



The one case which expanded to .4350" is troubling..  I believe the listed 7.0grs. is just about right.

[The_Shadow]

Great work RDub

[Rick R]

Great information. Thanks for taking the time to compile all that.

[RDub01]

Thank you. It was fun doing this..

Yesterday, I shot a group with the HAP bullet and 7.3grs of SR 7625.  Target at the end and new graph and spreadsheet.

[The_Shadow]

RDub have you ever tested SR 4756, it was said to be a great power in 357 Mag.  I have never had the chance to test these.
They are very close in comparison.  If I recall SR4756 was said to be going away according to Hodgdon.

Here is older load data I have for both the SR powders from IMR tested in 5.00" barrels

SR 4756
Rem 155 Gr   SR-4756    8.5   1310   Rem 2 1/2   Rem   34,400    1.250"
Win 180 Gr   SR-4756    7.6   1155   Rem 2 1/2   Rem   34,400    1.250"
Hornady 200 Gr   SR-4756    6.6   1045   Rem 2 1/2   Rem   35,800    1.250"

SR-7625
Rem 155 Gr   SR-7625   7.8   1275   Rem 2 1/2   Rem   34,300    1.250"
Win 180 Gr   SR-7625   7.0   1140   Rem 2 1/2   Rem   35,100    1.250"
Hornady200 Gr   SR-7625   6.2   1040   Rem 2 1/2   Rem   35,700    1.250"

[RDub01]

Hey Shadow
Well the focus here was on the faster powders, 4756 being more in the 'medium' class..  I have a little bit left.. I guess I could shoot a few just to say I did it..
I've yet to load any 4756 in a 10mm case.  From the loading data it appears it does well with 135/155gr bullets.
I used to use a lot of it in .38 Special +P loads.  It didn't perform at max levels in .357, (2400 being the powder of choice for that back then) and didn't produce very good groups as I recall, but worked well with 158gr cast .38 Special loads.
I tested some in the 10mm Short..(40 S&W) and got respectable velocity with decent accuracy. 

I'll gather some 180gr data and come up with a load..

[The_Shadow]

Cool deal, IMR SR 4756 has always intrigued me, as communications with others who said they liked the performance in other cartridges.  I had just never purchased any over the years...the data suggest that it stopped short of the upper end of pressure.
If you do test these I'll be interested to see the results.  If they are as good as they should be, I'll probably kick myself seeing that it may be discontinued by Hodgdon...

[Trapper6L]

Interesting. I'm new to the 10mm game. I bought a Remington R1 Hunter a month ago and have been playing with the bullets I had in stock. I've gotten great loads from Unique with the 135gr HPs and the Remington 155 gr HPs. Groups from bags at an inch at 25 yds. I just got in 500 180gr RN jacketed bullets so I'll be playing with the loads this week. Considering I'm sitting on a bunch of Unique, I'm hopeful the 180's do well with it. I've also gotten good results using Blue Dot with equally as good of groups. I would have thought CFE Pistol would be ideal but the accuracy just wasn't there for my particular gun. From your data it looks like you are running the ammo at max length. I load pretty much the same with the mag being the limiting factor. The 155 Rem HPs won't make max length and stack in the mag so I shorten them up to 1.250.

Probably a strange question but does anybody here load the 10mm for 100 yard shots? We shoot the 100 yd game with pistols. You certainly can tell what has any guts and what's a popcorn gasser. We also shoot 6" steel plates at 100. My shooting bud uses a Ruger 44 mag with full house loads. He rarely misses. I'm about a 60% shooter but getting better, I hope. We shoot all kinds of games including golf balls at 25 yds. That's a hoot!

[RDub01]

Hey Trapper welcome..
Haven't seen one of those Remington guns yet but they look pretty nice..  Maybe Remington will introduce a full power factory load now.. lol

If I was going to join in on what you guys are doing, I would bring some full power 200 grain rounds loaded with AA #9.  Magnus makes a pretty good bullet;

https://www.midsouthshooterssupply.com/item/00051j144/10mm40-caliber-point400-diameter-200-grain-truncated-cone-250-count

UNIQUE will give you a nice mid-range load with 180gr bullets, but nowhere near a full power load.  Blue Dot will get you there however. 

The 10mm is quite a hot rod..  Have fun and be safe..

[The_Shadow]

I used to shoot some of my most accurate 175 grain cast bullets over 10.4 grains of Blue Dot out to 130 yards from my S&W1006 with adjustable sights.  Keep in mind though these were all hand weighed loadings and much younger, stronger guy with eyes like an eagle back then.  Easily could bust clay skeet on the 130 yd. berm and clean up larger pieces.

Back in the early 90's (before I even had a Chronograph) I tried AA#7 and AA#9 and just could not get the accuracy I was achieving with my Blue Dot loads, even in other cartridges like 357 Magnum and 44 Magnum.

It seems now though I study, document, load and shoot more for upper velocity with reliability than accuracy.