Hodgdon Lil'Gun Works in the 10mm!

[Bringsteen]

THESE DATA ARE NOT FROM A RELOADING GUIDE. YOU ASSUME ALL RESPONSIBILITY CONCERNING YOUR USE OF THESE DATA.

After much theorizing, I decided to load Hodgdon Lil’Gun in the 10mm. My starting loads were based on a number of factors:
--maximum working pressure for the 10mm (which, at 37,500, is lower in practice than some people realize);
--Hodgdon’s various Lil’Gun loads for the .327 Federal, .38 Super, and .357 Magnum;
--total grain capacities of the 10mm and the above calibers; and,
--my experience with the 10mm’s slowest recommended powder, Accurate #9.

These factors do not add up to an ability to perfectly predict the outcome. But I am happy to note that not only was I able to complete the testing safely, but I came up with some rather promising results.

Components:
--Hornady 180 grain XTP bullets;
--New Starline brass;
--CCI 350 Magnum Pistol Primers.

Everything I read about Lil’Gun indicated that it requires a magnum primer and a heavy crimp. In preparing these loads, I seated and lightly crimped the bullets with a conventional seating/crimping die, then immediately put a heavy-duty crimp on them with a Lee Crimp die. I did the initial crimp before the heavy-duty crimp because some of the charges were slightly compressed. Incidentally, while Hodgdon has warned in the past that Lil’Gun should not be compressed, in the 2009 Hodgdon reloading manual Hodgdon published a compressed Lil’Gun load for the .38 Super. I loaded all cartridges to just under 1.26".

As a baseline, I fired two strings of high-power Accurate #9 loads on the same day as the Lil'Gun loads. All strings were fired in the same pistol, my Colt Delta Elite Gold Cup. I used a 24 pound Wolf recoil spring, coupled with the original recoil spring plug, which incorporates a smaller, secondary spring. My Delta Elite does not have a fully-supported chamber.


Accurate #9, 15 grains
_ 1)_1331.0_ -32.6 f
_ 2)_1366.0_ 2.4
_ 3)_1370.0_ 6.4
_ 4)_1373.0_ 9.4
_ 5)_1365.0_ 1.4
_ 6)_1354.0_ -9.6
_ 7)_1360.0_ -3.6
_ 8)_1368.0_ 4.4
_ 9)_1370.0_ 6.4
_ 10)_1379.0_ 15.4

__ High:_1379.0
__ Low:_1331.0
__ E.S.:_ 48.0
__ Ave.:_1363.6
__ S.D.:_ 13.3
__ 95%:_ ±10.0


Accurate #9, 15.5 grains
_ 1)_1393.0_ -7.9
_ 2)_1417.0_ 16.1
_ 3)_1398.0_ -2.9
_ 4)_1395.0_ -5.9
_ 5)_1405.0_ 4.1
_ 6)_1410.0_ 9.1
_ 7)_1399.0_ -1.9
_ 8)_1413.0_ 12.1
_ 9)_1396.0_ -4.9
_ 10)_1383.0_ -17.9

__ High:_1417.0
__ Low:_1383.0
__ E.S.:_ 34.0
__ Ave.:_1400.9
__ S.D.:_ 10.3
__ 95%:_ ±7.8

Hodgdon Lil’Gun, 15 grains
_ 1)_1219.0_ -19.8
_ 2)_1217.0_ -21.8
_ 3)_1260.0_ 21.2
_ 4)_1256.0_ 17.2
_ 5)_1265.0_ 26.2
_ 6)_1247.0_ 8.2
_ 7)_1242.0_ 3.2
_ 8)_1224.0_ -14.8
_ 9)_1233.0_ -5.8
_ 10)_1225.0_ -13.8

__ High:_1265.0
__ Low:_1217.0
__ E.S.:_ 48.0
__ Ave.:_1238.8
__ S.D.:_ 17.7
__ 95%:_ ±13.4

Hodgdon Lil’Gun, 15.5 grains
_ 1)_1250.0_ -5.3
_ 2)_1254.0_ -1.3
_ 3)_1267.0_ 11.7
_ 4)_1227.0_ -28.3
_ 5)_1286.0_ 30.7
_ 6)_1272.0_ 16.7
_ 7)_1266.0_ 10.7
_ 8)_1216.0_ -39.3
_ 9)_1238.0_ -17.3
_ 10)_1277.0_ 21.7

__ High:_1286.0
__ Low:_1216.0
__ E.S.:_ 70.0
__ Ave.:_1255.3
__ S.D.:_ 22.7
__ 95%:_ ±17.1

Hodgdon Lil’Gun, 16 grains
_ 1)_1282.0_ -4.5
_ 2)_1314.0_ 27.5
_ 3)_1282.0_ -4.5
_ 4)_1285.0_ -1.5
_ 5)_1304.0_ 17.5
_ 6)_1298.0_ 11.5
_ 7)_1253.0_ -33.5
_ 8)_1268.0_ -18.5
_ 9)_1279.0_ -7.5
_ 10)_1300.0_ 13.5

__ High:_1314.0
__ Low:_1253.0
__ E.S.:_ 61.0
__ Ave.:_1286.5
__ S.D.:_ 18.1
__ 95%:_ ±13.7

Hodgdon Lil’Gun, 16.5 grains
_ 1)_1246.0_ -47.7
_ 2)_1323.0_ 29.3
_ 3)_1286.0_ -7.7
_ 4)_1310.0_ 16.3
_ 5)_1320.0_ 26.3
_ 6)_1297.0_ 3.3
_ 7)_1286.0_ -7.7
_ 8)_1282.0_ -11.7
_ 9)_1273.0_ -20.7
_ 10)_1314.0_ 20.3

__ High:_1323.0
__ Low:_1246.0
__ E.S.:_ 77.0
__ Ave.:_1293.7
__ S.D.:_ 24.0
__ 95%:_ ±18.1


These results are quite promising. The fired brass and primers looked very healthy. As noted earlier, I fired these in a pistol without a fully-supported chamber. While I often see “Glocksmiles” (even though it is a Colt) when shooting high-power 800-X loads, there were none to be found from the Lil’Gun loads. An average of 1293 is nothing to write home about, particularly considering the 1400 fps average in the 15.5 grain Accurate #9 load. But the fact is that Lil’Gun works in the 10mm! I don’t have time right now, but I am interested in moving up .5 grain to 1 grain.

I hope that this information is valuable.

[AlaskaMike]

Thanks for posting this--I always find good, detailed experiments like this very interesting.

Mike

[Bringsteen]

AlaskaMike Thanks for posting this--I always find good, detailed experiments like this very interesting.

Mike

There are just not enough load data for the 10mm. Sometimes we have to find it for ourselves.

[bfoosh006]

http://stevespages.com/400p_3_180.html

Try here for data, its old school (start low and work your way up) but his pages are thorough.

[Bringsteen]

Those are some pretty good data. I just wish the companies would provide data on all the powders that have potential in the 10mm. Hodgdon Lil'Gun clearly works; Hodgdon should put it in their reloading guide.

[Magnum Wheel Man]

thanks for posting your well documented expiriment... I have both 10mm & 10mm Magnum & am currently loading Lil Gun & H-110 in 45 Colt +P loads looking for a good deer hunting Contender load... I'm not seeing a huge difference between the 2 but Lil Gun seems to offer a bit more heat... I've also noticed the velocity spread seems to be less with a good tight crimp ( which I don't necessarily do with the single shot Contender )... as the weather warms up I'll be pulling the Crony out & completing my tests... but so far I'm liking the Lil Gun in cartridges from 22 Hornet to 45 Colt...

[Bringsteen]

Have you used Lil'Gun in your regular 10mm? I am curious to see what results others have achieved.

[Magnum Wheel Man]

no... sorry... I won't get to the 10 or 10 mag exp's till next winter... too many to play with this year already...

[freakshow10mm]

Just want to caution new guys that the 15.5gr AA #9 load above is a full 2gr over published max load for the 10mm. Load with caution. Start at the start charge and work your way up. If you go into uncharted territory and venture past published max, it is 100% your risk and your fault if any injury or damage occurs.

[Bringsteen]

I second Freak's comments. I should have written it before myself.

15.5 grains of Accurate #9 is indeed a full 2 grains over currently published data. But as recently as 2004, the maximum #9 load under a 180 grain xtp recommended by Hornady was 14.9 grains. So 15.5 grains is 0.6 grain more than what used to be maximum. Nevertheless, 15.5 grains is a heavy charge for a notoriously hard-to-push bullet.

[WESHOOT2]

Might monkey about with a few fine Vihta powders......(suggest testing with various primers).....

[freakshow10mm]

Yeah, but most of us aren't rich like you.

[Bringsteen]

Vihtavuori powders are extraordinarily clean-burning and accurate, but none of them is going to give you maximum velocities. Vihtavuori pistol powders are all single-base, which means that they don't have any nitroglycerin mixed into the nitrocellulose. Double-base powders contain more energy per grain than single-base powders.

Both Accurate #9 and Hodgdon Lil'Gun are double-base powders.

[WESHOOT2]

Not "44 Magnum-like performance" (which I kept my 44 for).

(Plus I cannot ignore N105/N110/N350....)

[Alleykat]

AA#7 works great in 10mm also.

[Bringsteen]

The new data are interesting and a little confusing. Once again, I used 180 grain Hornady XTP's, new brass, handloaded each charge, and put a heavy crimp on the cases. As you can see, the 17 grain charges were slightly faster than the 17.5 grain charges.


Hodgdon Lil’Gun, 17.0 grains
_ 1)_1409.0_ 13.3
_ 2)_1402.0_ 6.3
_ 3)_1434.0_ 38.3
_ 4)_1371.0_ -24.7
_ 5)_1408.0_ 12.3
_ 6)_1397.0_ 1.3
_ 7)_1419.0_ 23.3
_ 8)_1373.0_ -22.7
_ 9)_1378.0_ -17.7
_ 10)_1366.0_ -29.7

__ High:_1434.0
__ Low:_1366.0
__ E.S.:_ 68.0
__ Ave.:_1395.7
__ S.D.:_ 22.9
__ 95%:_ ±17.3

Hodgdon Lil’Gun, 17.5 grains
_ 1)_1351.0_ -37.8
_ 2)_1399.0_ 10.2
_ 3)_1428.0_ 39.2
_ 4)_1414.0_ 25.2
_ 5)_1392.0_ 3.2
_ 6)_1337.0_ -51.8
_ 7)_1383.0_ -5.8
_ 8)_1381.0_ -7.8
_ 9)_1414.0_ 25.2
_ 10)_1390.0_ 0.2

__ High:_1428.0
__ Low:_1337.0
__ E.S.:_ 91.0
__ Ave.:_1388.8
__ S.D.:_ 29.8
__ 95%:_ ±24.3


What is frustrating is that the highest average velocity (1395.7) is actually lower than the highest average velocity using Accurate #9 (1400.9). But the maximum velocity with the Lil'Gun loads was higher (1434) than the #9 loads (1417). I will probably experiment with using a slightly lighter crimp and dropping down by a few tenths of a grain. It may be that compressing Lil'Gun in the 10mm doesn't do any good. Compression loads work for some powder/cartridge combinations, and not for others. I will also try to load them just a little bit longer, but the need for reliability dictates that I only stretch them by a few thousands of an inch, so it may not make any difference.

[Magnum Wheel Man]

the AA#9 is a faster burning powder & may produce better results in a "normal" length auto barrel...

I'm doing a lot of 10" Contender barrel loading for several calibers right now, & the Lil Gun seems to have the advantage at the 10" length... but that likely diminishes as the barrel length gets shorter...

I just reciently got my S&W 610 converted to 10mm Magnum, so I'm looking forward to playing around next winter with loads for both 10mm & 10 Mag in a 6" revolver... will likley find the Lil Gun a bit better for both, even though my last loadings of 10mm Magnum were done with AA#9 ( loaded before Lil Gun was available )

[Bringsteen]

I am doing my testing with a Colt Delta Elite Gold Cup. It has a standard 5" barrel.

I am very curious to see some results from someone using a 6" barrel.

[Magnum Wheel Man]

My Automag 4 has an 8" barrel, but only chambers the 10 Mag... the 6" revolver, won't be the same as an auto, as the cylinder holds the chamber ( so total length is actually longer ), & there is pressure loss at the barrel cylinder gap ( which equates to a loss of length ) I guess I've never seen a direct comparision to see if the gap loss equate the extra length of the cylinder ??? I'd suspect it is somewhere around a loss of 1/2 the cylinder ???

also the revolver now chambered for 10 Mag has some freebore before engaging the throat, with the 10 mm, so it could lower "chamber" pressures some ??? I hope to get my sights of choice on the gun this summer & plan to pretty extensively test both the 10mm & 10 mag in the revolver & alittle bit with the 40 S&W, to see if I can pick a bullet style or load that still shoots OK in the gun ( normally the 40 S&W shoots pretty good in the stock 610, but there is very little real length difference between those cases... the 10 mag case is like over 1/4" longer than the regular 10mm so the 40 S&W has a lot of freebore in my revolver )... I'd also like to do up a load that would shoot equally well in either the Automag or the revolver, & the Lil Gun seems like a natural to expiriement with...

BTW... I'm shooting 190 & 200 grain bullets in 40 cal, & my understanding is the Lil Gun's benifits increase as the bullet weight does, so again, it should be a natural for heavier 40 cal bullets...

[Shoney]

Bringsteen
I think you would have reasonable data if you had pressure sensors data. I would wager that if you were to get actual pressure data for your loads, you would instantly end any constipation problems you might have.

[Sevens]

As one of those guys who simply doesn't need max loads, let alone unpublished loads, I probably don't even belong in this thread. Still, though, I find the posts and data and research very interesting, even if I have no real use for it.

In any case, isn't diminishing velocity from a heavier powder charge one of the telltale signs of high pressure?

[Bringsteen]

I wish I had pressure testing equipment. That way, I could find a maximum load that would fall within the 37,500 psi working pressure limit. But given the fact that the powder capacity of the 10mm is smaller than the standard magnums (.357, .41, .44), and the fact that Hodgdon Lil'Gun is slower than any other powder indicated for use in the 10mm, it approaches statistical impossibility that I could construct a load that would exceed burst strength.

My system of pressure evaluation, although low-tech and nowhere near as good as actual pressure-testing equipment, is rigorous. I have several strings of spent cases from various factory loads and hand loads. Included in these is a string of very heavy IMR 800-X loads. These are threshold loads--right at the point of bursting. I compare the loads I am testing to these earlier factory and handloaded strings. I compare the relative primer flatness. But more importantly--and more objectively--I compare casehead expansion using a micrometer.

None of the Hodgdon Lil'Gun loads have even begun to indicate severe pressure.

Diminishing velocity can be a sign of high pressure. Once I started getting lower velocities, I knew I had probably reached the point of diminishing returns.

I realize that it is always somewhat risky to develop a new load without guidance from the powder company. But proper precautions go a long way.

[WESHOOT2]

You noted the 17.0g load was 'faster' than the 17.5g load.

Don't you wonder why?



I suggest that 17.0g load is at or very very near MAX (not certain which direction), and as you've added more powder your pressure increase is creating a dynamic during combustion that raises pressure but lowers velocity.

I been wrong before.

[Magnum Wheel Man]

I'm finding H-110 to "nearly" mirror the Lil Gun loads there are a few differences though... have you thought about trying it to see how it works in the 10mm ?? I'd be curious as to how / if it performs differently in the hotter loads... ( H-110 & Lil Gun are both my choices as I near finalizing my +P+ loads in my 45 Colt Contender for a hunting round )... AA#9 was dropped, not from lack of performance, but because it did not fill the case enough

I also load 50 AE for my Automag 5 & I added a "shortened slightly" 50A.E. "special" custom 5 shot Blackhawk revolver to my syuff a couple years ago, that I bought from a buddy along with all the reloading stuff for that one, I used AA#9 in the 50 A.E., & am looking forward to trying some other powders in both 50's ( again, I like my cases a little fuller if possible, & the AA #9 doesn't fill up the 50 cases as much as I'd like, so I'll probably want to do an H-110 / Lil Gun expiriment there as well...

[SL1]

From what you have told us so far, it looks like the 17.5 grain load is the first string that was a compressed charge. If so, it makes sense that it might be having some ignitiion difficulty when compressed, giving lower velocity, on average, but having a higher extreme spread. The spread increases mostly in the downward direction, which says "ignitition issue" to me.

For what it is worth, Hodgdon's rep on the telephone told me NOT to compress Lil'Gun. He said sometimes it slowed the effective burn rate, but every once in a while it would all ignite well and give a pressure spike.

I took a look at your max charge in QuickLOAD using default values where you did not give data (such as case volume), but got obviously incorrect results (297,000 psi). I think we can all agree that is not what your gun is producing, or you wouldn't be typing these posts. If I increase the case capacity by 15% from its default value, I get the pressure down to the SAAMI limit, while still showing a compressed load. I am not sure whether that is realistic.

I have a continuing problem with Lil'Gun in QuickLOAD for the .357 Magnum, even though I have all the data that I need to specify the parameters for that load. I simply cannot match Hodgdon's published data with the program. Strangely, it does work for the .44 Magnum. So, I don't think we can expect to get something for the 10mm that you should rely on from QuickLOAD with Lil'Gun.

I have talked to Hodgdon about the discrepencey with the .357 Magnum, but they have not wanted to even begin thinking about the computing aspects of the issue. They believe their test data, and don't want to think about any changes in burning characteristics between cartridge applications that seem to be indicated by the computations. They just say "What's news about that?" and don't try to understand further.

I was trying to understand further because I have seen some published Lil'Gun loads fot the .357 Magnum that have unexpectedly high velocity, but were not pressure tested to assure me that the pressures were not also unexpectedly high.

So, in your case, I just want to tell you that you might not be able to adequately predict the beahvior of Lil'Gun in the 10 mm case by extrapolating from its behavior in other cartridges. That is essentially what QuickLOAD does with some pretty complicated math, and it isn't working very well at all.

Measuring case head expansion is a smart thing to do, but it is an irratic phenomenon at 37,500 psi. Some cases may expand substantially more than others when subjected to the same pressure. And, you need to use virgin brass for each shot, because it will not expand again at the same pressure, next loading.

I do look at it, but also at the pressure ring diameter. In 35,000 to 45,000 psi cartridges, I find that I get better data from pressure rings than from case heads. And, I can shoot the same case more than once and get relative differences for two loads using the same case. I have been planning (for years) to develop some useful data on how the pressure rings change with repeated firings of the same case with the same load, because I have not seen that anywhere. It may depend somewhat on how you size the brass, as well as how many times the cases have been fired. Without that information, I tend to do a lot of comparisons with a lot of cases. My gold standard for comparing two loads, one pressure-tested and one not, is to compare pressure ring diameters for 10 cases, each fired their second and third times for the test, with 5 using the pressure-tested charge first and 5 using the unknown charge first. (All used the same charge for their first firing, and the 10 cases were selected for uniformaty of the rings around their circumferrences as well as similarity of their average diameters.) That is a lot of firing to get some idea of what the comparison is between a pressure tested load and another load.

I am enjoying watching your progress, here. Just please be careful about your assumptions. Those are what usually get us into trouble.

SL1