Lil'Gun and Your Forcing Cone?

[jski]

I've read some things about Lil'Gun being "hard on your forcing cone"? What's up with this? Is it any "harder on your forcing cone" than H110?

[jski]

Lil'Gun damages your forcing cone:

Bob Baker’s, from Freedom Arms, comment from a quote in an older post from the Ruger Forum.

https://www.rugerforum.net/threads/l...rifles.360363/

Direct links seem to all be dead.

"We have seen numerous barrels damaged by using Lil Gun. According to customers, some had as few as 30 rounds using Lil Gun through them, some had several hundred. Before we figured out what was happening one customer had sent his gun in for a new barrel. Then 600 rounds later it came back for another new barrel.

A couple years ago we did a test with a M83, .357 Mag. using Hornady 180 gr. bullets. We loaded 50 rds. of three different loads. One was a heavy H-110 load and the other two both used Lil Gun in different quantities.

We fired the H-110 loads first, then cut off the threaded end of the barrel. Rethreaded the barrel and shot one of the Lil Gun loads then rethreaded the barrel and shot the last Lil Gun load.

We found even the light load of Lil Gun caused the gun to get extremely hot. The heavy Lil Gun load had the gun so hot the only place we could touch the gun was on the grips and they were very hot.

Under magnification the surface appeared to have heated to a point of flowing using the Lil Gun loads and the heavy load was worse than the light load. This is probably due to Lil Gun having about 10% more nitro glycerin in it than H-110.

Yes it applies to the .475 also. I intentionally ran the tests with a cartridge that is less pressure than the 454 just to make sure.

I have also heard of problems with rifles but I haven't tried to verify it by running my own tests."

[HiBC]

Interesting heads up.

When I built my 300 BLK ,Lil Gun looked good on paper. I saw a chance to buy 4 lbs of Lil Gun so I jumped on it.

I have not loaded any yet.

No disrespect to your post, jski,I'm grateful and I'm paying attention, but I don't necessarily jump to a conclusion over an internet post or two.

I'm going to follow this post and see how it plays out. I'm happy to learn something and I'd rather scrap the powder than the barrel

Thanks!

[jski]

This post is a question, not a statement.

[HiBC]

Fair enough. I'm grateful for the question.(

This post is a question, not a statement.

)

You might want to add a little statement of context to the bare link above or it will likely get zapped for being a drive by. Its a useful contribution to the discussion. The "Iowan's" post is worth reading. He seems to be a good source of tech knowledge.

I do not doubt Freedom Arms concerns. They sure made fine revolvers.

At this point,I would be very reluctant to use Lil Gun in my revolvers. For now.

The issue appears to be gas cutting. I've seen gas cutting on an AR firing pin tip from less than 10 rounds of pierced primers. I was looking with 10x magnification and it was minor,but it was there. Leaking primers can gas cut a bolt face really quick. Gas cutting is real.

It MIGHT be (I'm not sure) that this is about cylinder gap and gas bypass at the forcing cone, as the contributor to your linked forum explained.

It MIGHT be that under rifle conditions,without the gas jetting,it would not be an issue for an AR 300 Blk. I wonder about the gas port.

For now,my LilGun will stay in the jug,but I'm not ready to pour it on the lawn.

I hope Unclenick weighs in. He is a great source of knowledge and clear thinking.

[MarkCO]

I've shot thousands of rounds of 300BO, 450BM, .41 Mag and .414 SuperMag loaded with Lil Gun, no issues at all

[Unclenick]

The heating of the gun reported by Freedom Arms is interesting. A lot of folks also complain that Tight Group heats guns excessively, though it's not a slow powder. Modern research on barrel erosion (something constantly funded by the world's militaries, particularly for artillery) indicates the rate of damage and the level of heat stress are affected by the balance of gas species that result from a powder's combustion, with those that produce a larger portion of higher density gases tending to heat the guns by higher rate of heat transfer at all temperatures and increase the barrel erosion rate. So while nitroglycerin content can explain why Li'l Gun has more total energy content and peak temperature, that may not be directly responsible. The Executive Summary in this Australian Defense Force paper from 2005 states in part:

"In the past it is has been commonly held that hotter-burning gun propellants are more erosive, however this is not always true. A significant number of cases have been reported where erosion does not increase with flame temperature, and chemical attack of the bore by propellant gas species has been the primary determinant of erosivity."

This outfit actually has a bore erosion-limiting paste. From its description, it appears to be a phase-change material that coats the bore and can absorb some energy (though it may have additives that bind to some combustion products, too; I don't know). Waxes fall into the phase change material category. Years ago, a retired military armorer told me 1911 45 auto barrels would last about 25,000 rounds with hardball, but that he'd seen softball barrels that were still shooting fine well over 100,000 rounds later. So, as cast bullet shooters go full-tilt boogie into powder coating, it may be the old smokey wax-based bullet lubricants have been extending bore life all along. It would be interesting to see how Li'l Gun behind lubricated cast bullets compares for erosion to using it with bare or powder-coated bullets, but I can't think of any matched sets of guns I want to donate to conducting that experiment. In fairness, I should point out a lot of the powder coating materials can act as phase change materials, too, but they don't normally leave a coating on the bore.

[Shadow9mm]

I have fired probably 100 full powered loads of 357 with lil gun, never had any problems.

[TX Nimrod]

I don’t use Lil’Gun in my revolvers, but do so in my .300 BO. The barrel temps are noticeably higher with LG than with H110. Next time I take it out I’ll bring the IR gun and take measurements.




.

[jski]

MarkCO, it's hard to argue with empirical evidence like that. Empirical evidence trumps opposing "claims" every time.

[reynolds357]

Originally Posted by jski

MarkCO, it's hard to argue with empirical evidence like that. Empirical evidence trumps opposing "claims" every time.

I have run at lear 2500 LilGun loads through my 450Bushmaster AR upper. It still looks and shoots new.

[zeke]

Big difference in shooting lil gun in a rifle, and shooting through a revolver. Like apples and oranges.

Tried Lil-gun in 32 mag for the reported max velocities when it first came out. Got the velocity's and ex accuracy. Through a 32 mag ruger ss revolver started getting forcing cone erosion in under a dozen rounds. Not serious disabling erosion, but easily visible. Used Lil gun again in 357 marlin lever, and got no discernible affects. Again got best velocity and accuracy with Speer's old 170 fsp.

Have several 357 mag revolvers that have minimal throat erosion, but not with lil gun.

These are statements, not questions.

[jski]

What does this "damage" look like. I've fired 100 rounds of .32 H&R with max loads (using XTP 85 and 100 grain bullets) through my Blackhawk with a 6 1/2" barrel. I see no signs of any damage. Compared it to my .30 Carbine Blackhawk and see no difference. I load my .30 Carbine rounds for the Blackhawk using heavy 120 gr bullets on top of H110. Again, neither appear "damaged".

I'd love to see this "damage". I'm from Missouri: "SHOW ME!"

[zeke]

A super single is not a black hawk, and really don't give a damn what you demand/want. Or where you live. It looked like forcing cone erosion, if you have ever seen it.

[reynolds357]

Originally Posted by zeke

Big difference in shooting lil gun in a rifle, and shooting through a revolver. Like apples and oranges.

Tried Lil-gun in 32 mag for the reported max velocities when it first came out. Got the velocity's and ex accuracy. Through a 32 mag ruger ss revolver started getting forcing cone erosion in under a dozen rounds. Not serious disabling erosion, but easily visible. Used Lil gun again in 357 marlin lever, and got no discernible affects. Again got best velocity and accuracy with Speer's old 170 fsp.

Have several 357 mag revolvers that have minimal throat erosion, but not with lil gun.

These are statements, not questions.

Why is it different? A chamber throat is a chamber throat.

[jski]

Zeke, cool your jets dude. Lighten up.

"I'm from Missouri, show me!" is an expression. I'm not really from Missouri. And no, I don't know what this damage looks like, that's why I asked someone to show me.

This is the forcing cone for my .32 Blackhawk:
FC.jpeg
It looks the same as my .30 Carbine Blackhawk, assuming that's ok.
This is a new Blackhawk.

[jski]

Quick observation: the burn rate for Lil'Gin is 85th and H110 is 87th on loaddata.com, where Norma R-1 is 1st (fastest) and Vihtavuori 20N21 is 197th (slowest). So both Lil'Gun and H110 are in the bottom 1/2 of powder burn rates where pistol powders reside.

The burn rate will tell you how long the powder continues burning in the barrel, so maybe if it’s burning all the way down the barrel, it heats up the barrel more. But the problem is what happens in the beginning when the bullet’s jumping from the cylinder into the barrel.

[Sevens]

I love evidence and reports from folks that have used it. And I don’t begrudge them for their choices.

I used it for a short time in .357 Mag and got some fantastic velocities… and I stopped using it when I read reports from Freedom Arms.

Freedom revolvers are absolutely fantastic. And while there COULD be another and there MIGHT be another, I cannot sit here and from memory come up with one single other gunmaker that not only doesn’t warn owners that their handloads are potentially “dangerous” and may void warranties… Freedom Arms knows damn well their buyer are going to handload for their revolvers.

They even go as far as to sell component brass. At least they did at one time, because I bought some directly from them.

Every gun maker I’ve ever seen takes the lame stance that handloaders are all your idiot brother in law, but Freedom Arms supports the end buyer in his handloading ventures in their guns.

So then

When Freedom has something to say about one particular powder showing nearly instant damage in arguably the finest single action revolvers ever mass produced, I’m choosing exactly that as the evidence I’ll trust.

Especially when I’m not stuck on a deserted island with only Lil’Gun, as it seems I’ve got five other slow burning magnum handgun powders here at home with God knows how many others on the market I could also choose from.

I sold my 7 leftover pounds of Lil’Gun to a local buddy with full disclosure and he loaded it in .300 Blackout.

[zeke]

Originally Posted by reynolds357

Why is it different? A chamber throat is a chamber throat.

Perhaps looking at revolver's cylinder gap might be a start for ya. Pretty obvious difference.

[zeke]

Originally Posted by jski

Zeke, cool your jets dude. Lighten up.

"I'm from Missouri, show me!" is an expression. I'm not really from Missouri. And no, I don't know what this damage looks like, that's why I asked someone to show me.

This is the forcing cone for my .32 Blackhawk:
Attachment 114996
It looks the same as my .30 Carbine Blackhawk, assuming that's ok.
This is a new Blackhawk.

pretty easy to google

[jski]

Has any other wheelgun manufacturer (besides Freedom Arms) issued a warning about Lil’Gun?

[FrankenMauser]

I have used Lil Gun in .300 Blackout, .44 Mag, and .327 Federal; and it was the dominant powder in .458 SOCOM for several years (90-95% of my loads).
Probably somewhere in the range of 500-750 rounds, total.

I never saw any measurable impact on the revolvers and rifles.
They did, however, get hot a lot faster than with loads using other powders.

I have stopped using Lil Gun in metallic cartridges. What I have remaining has been set aside for .410 and similar shot shell loads.

Heat is bad. Why keeping using something less than ideal, when there are other options without the risk?....

[Shadow9mm]

Originally Posted by FrankenMauser

I have used Lil Gun in .300 Blackout, .44 Mag, and .327 Federal; and it was the dominant powder in .458 SOCOM for several years (90-95% of my loads).
Probably somewhere in the range of 500-750 rounds, total.

I never saw any measurable impact on the revolvers and rifles.
They did, however, get hot a lot faster than with loads using other powders.

I have stopped using Lil Gun in metallic cartridges. What I have remaining has been set aside for .410 and similar shot shell loads.

Heat is bad. Why keeping using something less than ideal, when there are other options without the risk?....

Sometimes you dont have options. When i started using lil gun i could not get H110. Yes it gets my gun hotter faster. However when dealing with hunting loads that i dont rapid fire, and only shoot 50-100rnds a year of, it works just fine. I do use and prefer h110, but i have no problem using lil gun either.

[FrankenMauser]

When I started loading .458 SOCOM, there was a two-fold reason for Lil Gun:
1. It was all I could get.
2. It had the most data (lucky me).

But I have better options now.
No point in going with "hot" when I can choose something potentially less damaging.

[MarkCO]

IF temp is the only issue, there are hotter (temp) powders for sure that don't cause problems. The reports of erosion after only a handful of rounds may be hyperbole, but really, you are not going to get flame cutting from the max temp that LilGun can burn in the range of pressures by shooting single rounds. There is just not enough energy to heat up even a very thin forcing cone.

Thin forcing cones, larger cylinder to cone gaps and shooting cylinders full at a time, depending on the material and heat treat of the forcing cones, one could get there.