180gr bullets over Longshot

[Turo]

Since there aren't too many topics yet, I figured I'd throw some reloading data into this forum.

I load 10mm with Hodgdon Longshot powder and usually 180gr Precision Delta bullets. For developing loads (all posted here are my development loads) I use new starline cases and CCI large pistol primers.  Hodgdon's data suggests between 8.5 and 9.5gr for the 180gr FMJ, but their data indicates only 34,600 psi for the max load and I wanted to see what i could do to outdo them.  For all my tests I used a stock Glock 20sf with the stock 4.6" barrel and stock recoil spring.  All rounds were loaded to an OAL of 1.264 inches.  Of course, use this data at your own risk.  Reloading is dangerous, you'll probably blow yourself up, and all that legal stuff. 

Here's my data, complete with chronograph info.

8.5gr Longshot gave 1150 fps average.  Recoil was almost non-existant, and cases ejected about 4 feet away.

8.7gr Longshot gave 1160 fps average.  Recoil was again almost non-existant, but case ejection was erratic (some launched out 10 feet, and others fell directly at my feet.)

8.9gr Longshot gave 1165 fps average.  Recoil was a bit more than the previous two loads, but still nowhere near what a 10mm should give.

9.1gr Longshot gave 1188 fps average.  Recoil felt exactly the same as the 8.9gr loads.

9.3gr Longshot gave 1205 fps average.  Recoil felt nice and solid, like a warm 40S&W out of a small gun.  I haven't shot "full power" 10mm yet, but I would imagine the recoil these gave was a good "medium."

9.5gr Longshot gave 1213 fps average.  Recoil was like the 9.3gr load, a nice and solid medium 10mm. 

I should warn you, Hodgdon suggests 9.5gr with 180gr bullets as the max they should be loaded.  They list the pressure of these 9.5gr loads at 34,600 psi which is almost 3000 psi below the SAAMI specification for 10mm, so I went higher.

These next loads are not suggested, as they are above maximum book levels.  They are provided for information only and if you try them, don't blame me if you come back with less fingers than you had before.

9.7gr Longshot gave 1247 fps average.  Recoil has started to reach the point where it definitely feels like you are shooting 10mm and not just hot .40S&W.  That said, the recoil isn't unmanageable at all.

9.8gr Longshot gave 1260 fps average.  I have to note here that the extreme spread of this load was only 6 fps.  The others all were much larger (15-40 fps spread between max and min.)  The recoil was still not "stiff" but I wouldn't hand it off to a 90lb new shooter either.

9.9gr Longshot gave 1260 fps average again.  It almost seems like Longshot has been tapped out at this level as average velocities don't rise much after this, but I haven't gotten any pressure signs even up to the next load at 10.0gr.

10.0gr Longshot gave 1262 fps average.  This is as high as I went on the last outing, and I'll go higher after a while since I haven't seen any pressure signs yet.  The recoil of these loads definitely got my attention.  It seems like this is the recoil often talked about when discussing "full power" 10mm ammo.  The sound alone was incredible and probably added to my perception of the recoil.

Almost forgot to add:  I have not seen a "bulge" in any of these cases, and every single one of them has been reloaded and seems fine to shoot again.

Well, that's all I have for now.  I hope this info is helpful to somebody, somewhere.  It was fun for me to test, and I'll be adding more after I get out to test some more.

Happy Reloading!

[firebirdv8]

I make a medium power 10mm load with the same 9.3 gr load as you. I use plated 180 gr bullets from Ranier instead, but they probably shoot basically the same. Its a nice all around fun load to shoot at the range, and it does get attention.

Keep us updated on your continued results.

[alwaysshootin]

I've been reloading lead almost exclusively, and have only been loading 200 grain bullets to date. Mostly built up a hunting load out of my G20 with a 6" Lone Wolf barrel. Sold it along with my LW longslide. Recently picked up the LW 5.15 inch barrel to replace, and just drop in my G20.

   Haven't chronographed the new barrel with my load of 8.2 grains of Longshot, but achieved 1250 fps with the 6" barrel. I recently also picked up some 180 lead bullets and will work up a load or two with them. Usually one is to maximize power, and the other somewhat reduced, and attempting maximum accuracy.

  I'm trying to find the perfect lead bullet to shoot out of my 10, and 40's, so when it comes time to purchase molds, I only need one for each caliber I'm shooting. Have three of my calibers narrowed down, with the 10, I'm still experimenting to see which works for a do it all bullet weight!

[sqlbullet]

Have any of you been measuring case heads?  Without access to pressure gear that is about as good as it gets in estimating pressure. 

I generally start a test session with some buffalo bore rounds that I know are hot, and measure the heads as a baseline for the day.  Then anything that exceed those measurements by more than .001" is definitely a max load.

[Turo]

Have any of you been measuring case heads?  Without access to pressure gear that is about as good as it gets in estimating pressure. 

I generally start a test session with some buffalo bore rounds that I know are hot, and measure the heads as a baseline for the day.  Then anything that exceed those measurements by more than .001" is definitely a max load.

I have measured some, and the max I get is .433 I think. Don't quote me on that as I don't have any of them with me, but IIRC the biggest expansion I got was smaller than any max load I've ever seen reported on glock talk.

[sqlbullet]

That is still a fair bit of expansion.  Of course, the chamber of the gun impacts that a bunch too.  Which is why I usually fire some Buffalo Bore to start as kinda a control measurement.

[Turo]

That is still a fair bit of expansion.  Of course, the chamber of the gun impacts that a bunch too.  Which is why I usually fire some Buffalo Bore to start as kinda a control measurement.

You're right, I forgot to mention that even my lightest loads gave that same expansion.  I'm hoping to order some Underwood or buffalo bore sometime in the near future so I can get a max baseline.

[The_Shadow]

LongShot is a great powder, Mike McNett of Double Tap uses it and Mike Willard Of SwampFox used in his stuff and I would not be at all supprised if Kevin of Underwood Ammo is using the LongShot Powder.  It meters well and has a great yield for the amount of powder used especially in 10mm.  I've loaded some of the Hornady 200 gr XTP's with it @ 1200+ fps.
It is what I use for the 9x25Dillon project with several bullet weights.
I've also shot plenty of Blue Dot loads over the many years...

[sqlbullet]

I think I have some free time tonight.  Gonna break out the new brass and start some longshot loads under 205 grain lead RFN.  Hopefully I can get up to the range and try the new chrony with these loads this weekend.

[Taterhead]

That is still a fair bit of expansion.  Of course, the chamber of the gun impacts that a bunch too.  Which is why I usually fire some Buffalo Bore to start as kinda a control measurement.

You are exactly right. Buffalo Bore is a great comparison since they use Starline Brass commonly used by use 10mm hand loaders.

Maximum case expansion from BB loads is a hair under 0.434" in my G20 chamber. Expansion beyond that = Glock smiles (frowns really) that, fortunately, have been extremely rare in my pistol.

Start loads typically expand new Starline brass to 0.431", medium .0432, warm 0.433, and max loads approach 0.434". This has been true for dozens of load workups with different components for my G20.

[Turo]

That is still a fair bit of expansion.  Of course, the chamber of the gun impacts that a bunch too.  Which is why I usually fire some Buffalo Bore to start as kinda a control measurement.

You are exactly right. Buffalo Bore is a great comparison since they use Starline Brass commonly used by use 10mm hand loaders.

Maximum case expansion from BB loads is a hair under 0.434" in my G20 chamber. Expansion beyond that = Glock smiles (frowns really) that, fortunately, have been extremely rare in my pistol.

Start loads typically expand new Starline brass to 0.431", medium .0432, warm 0.433, and max loads approach 0.434". This has been true for dozens of load workups with different components for my G20.

Hmm, maybe I'm measuring mine wrong.  Am I right in saying that to measure the "bulge" you should measure the largest diameter of the wall of the case not including the rim?  Because measuring even "mild" 1150 fps loads I had expansion right at .433 inches.  I guess every gun is a little different, but I wouldn't think the chamber tolerances would be as big as 1 or 2 thousandths.  Measuring the chamber of my particular barrel, I get exactly .4340 inches if that helps.

[sqlbullet]

I generally measure with the lower edge of the caliper about the width of the caliper above the top edge of the case rim, if that makes sense.  I want to measure how much the web/brass base expands.

[Turo]

Okay, that sounds like I was doing it the right way.  I need to order some Buffalo bore or Underwood ammo so I can get a baseline for brass expansion it sounds like.

[Breadman03]

Okay, that sounds like I was doing it the right way.  I need to order some Buffalo bore or Underwood ammo so I can get a baseline for brass expansion it sounds like.

OT
I just subbed to your channel.  Guns, engineering, and dogs sounds like a good combo.
/OT

I'm in NE PA, and if anyone local wants to run some loads over my chrono, we can arrange a meeting nearby.

[Turo]

Okay, that sounds like I was doing it the right way.  I need to order some Buffalo bore or Underwood ammo so I can get a baseline for brass expansion it sounds like.

OT
I just subbed to your channel.  Guns, engineering, and dogs sounds like a good combo.
/OT

I'm in NE PA, and if anyone local wants to run some loads over my chrono, we can arrange a meeting nearby.

Thanks!