What is your favorite mild to medium 10mm loads?

[Dieselman]

  So I have been loading the 10mm for about a year now.  My loads during this time have been aimed at squeezing performance out of this cartridge.   Mostly 180 grain bullets at 1250fps to 1320 fps.  I am starting to get quite an accumulation of used brass that I no longer want to push to higher pressures.  So now I'm looking to start loading some milder 10mm loads that I can utilize my plinker brass in.  Got any favorite mild to mid level 10mm recipes that you use for brass relegated to plinker duty that you wish to share?

[fltbed]

180 gr. coated lead
6.8 gr WSF
CCI #300 primer
OAL 1.255

Chronos around 1100 f.p.s. and still cycles all my 10's.

Jeff

[sqlbullet]

6.7 grains of Unique under whatever 170-180 grain bullet I have around.  Produces about 1050 fps in a 5" barrel.

[DM1906]

It depends on what you mean by "plinker". For me, it's economically based, in that, higher volume of rounds, with lesser cost bullets and (infrequently) powder charges. There will be little pressure difference, if any, between full power and "plinker" loads. If your goal is lesser pressure and lesser velocity, then just down-load your current favorite full power load.

If your goal is to reduce the stress on the brass, then going to a faster powder at lower velocities won't (normally) do that. Faster powders are, well, faster. That means the powder must perform its task in a shorter period of time, which shortens the peak impulse period. Ultimately, you may be subjecting the brass and pistol to higher peak pressures, although felt recoil and velocity may be less, compared to your "full power" loads.

All that said, I've reused 10mm brass dozen(s) of times, with little, if any, indication that rounds loaded within maximum rated pressure reduce the reload count. Loading to overpressure levels (which I do, frequently), of course, changes that. Many handloaders falsely believe it's OK to load "full pressure" rounds to the point of visibly stressing the brass. If the brass is bulging, smiling, or deforming, it is over-pressure for the platform, although it may be well within the maximum limit for the cartridge. Firearms engineers do not design a firearm with the intent of preserving the cartridge case for the purpose of reuse. NONE of them. In fact, every major firearms manufacturer includes a printed disclaimer, stating that the use of "reloaded" ammunition will void any warranty. Of course, we do it anyway, they know it, and will rarely deny a claim unless it's blatantly obvious that you irresponsibly blew up your gun.

[Dieselman]

It depends on what you mean by "plinker". For me, it's economically based, in that, higher volume of rounds, with lesser cost bullets and (infrequently) powder charges. There will be little pressure difference, if any, between full power and "plinker" loads. If your goal is lesser pressure and lesser velocity, then just down-load your current favorite full power load.

If your goal is to reduce the stress on the brass, then going to a faster powder at lower velocities won't (normally) do that. Faster powders are, well, faster. That means the powder must perform its task in a shorter period of time, which shortens the peak impulse period. Ultimately, you may be subjecting the brass and pistol to higher peak pressures, although felt recoil and velocity may be less, compared to your "full power" loads.

All that said, I've reused 10mm brass dozen(s) of times, with little, if any, indication that rounds loaded within maximum rated pressure reduce the reload count. Loading to overpressure levels (which I do, frequently), of course, changes that. Many handloaders falsely believe it's OK to load "full pressure" rounds to the point of visibly stressing the brass. If the brass is bulging, smiling, or deforming, it is over-pressure for the platform, although it may be well within the maximum limit for the cartridge. Firearms engineers do not design a firearm with the intent of preserving the cartridge case for the purpose of reuse. NONE of them. In fact, every major firearms manufacturer includes a printed disclaimer, stating that the use of "reloaded" ammunition will void any warranty. Of course, we do it anyway, they know it, and will rarely deny a claim unless it's blatantly obvious that you irresponsibly blew up your gun.

I certainly agree with all you said here regarding pressures and powder burn speeds.  I was loading up some test rounds last night to shoot across the chrony with the goal of producing a lower pressure load in my used brass.  My used brass doesn't appear to be damaged. I don't have any sort of bulges or smileys or what not. Primer pockets still feel snug and proper.  I just feel like for safety, after loading hot loads in brass 2 or 3 times that I would be more comfortable with any future loads in that brass to be reduced pressure. And hot loads will be loaded in new brass or once, maybe twice fired brass. 

  Along the same lines of thinkin that you mentioned with fast burning powders and quicker peak pressures, I chose to load my test rounds with reduced charges of Longshot.  A 9 grain charge of Longshot gives me 1300 fps from my Kimber TLE with 180 gr. HST bullets.  I didn't save my notes of lesser charge weights of Longshot when I worked that load up. So last night I started at 8.8 grains and worked backwards in increments of .2 grains to 8.4 grains of Longshot to test. I would like to see velocities fall to about 1100 - 1150 fps or so with this combo. 

   While I was at it, I also loaded up a handful of 180 HST's with 5.6 grains of Titegroup. I don't really plan on loading any sort of quantity with Titegroup due to its fast burning speed and quicker pressure peaks. I guess I only did this test out of curiosity to see what velocities it shoots across the Chrony.  Even though a slower powder at reduced charge weights would likely be easier on the brass than the sharp rap given by Titegroup.

[The_Shadow]

Yes DM1906 & Dieselman, that was my contention as well, we see lots of people pushing the faster powders thinking they are being inside the pressure limits and safety.  However like you all discussed the instantaneous snap rather than the smoother outward push can be detrimental to brass more so than the upper pressure limits with slower burning powders.

This held true for why I used Blue Dot over the years as it was an excellent balance of velocity and accuracy vs. maximum pressure (usually at lower pressures than many other powders and same or near velocities).

My plinking play with 10.2 grains to 10.4 grains under the 175-180 grain bullets has been very easy on my brass.  Yes this is a fair amount of powder and economy for powder use lacks somewhat.  This has been another reason I started using some Power Pistol and more recently BE-86 in the economy loads...making use of the 40S&W brass in conversion barrels has also proven to build target trigger time and proficiencies from the same feel appeal 10mm guns and sight pictures.

Just understand an watch out for "WORK HARDENING" as you reuse the brass over and over.  This stiffening of the brass alloy can get to the point where the casing will not hold the resized dimensions and loose bullet fit can occur.  A bullet set back can happen if it goes unnoticed.  The use of cast bullets at 0.4015" - 0.4020" diameters may slightly offset the work hardened effects with the brass casings.

[DM1906]

Personally, I wouldn't consider the HST in the "plinker" category, and wouldn't waste time downsizing with that bullet (like filling your Lamborghini with E85). That's just me. However, 5.6 gr. Tightgroup is pretty light, even for a light load. Tightgroup is a good, economical powder, but expect well short of 1100 FPS. 6.0 gr. should get you to 1100 FPS, but once again, the pressure there will be close to that of slower powders at much higher velocities. Ultimately, velocity accomplished, pressure failed. What you are doing with Longshot, however, will be a win-win, except in the economics. In my experience, loading too low with Longshot did get a bit dirty, but you should be able to find the sweet spot you are looking for before getting to that point. I would recommend working up/down with magnum primers, as lesser case fill, especially with most magnum-type powders (such as Longshot), tend to lead to less consistent ignition with standard primers. Tightgroup, on the other hand, won't care which primer you use, although magnum primers are not recommended.

[Dieselman]

DM1906, I tend to agree that using my HST's as a "Plinker" isn't a good choice.  I only used them for this particular test because they were the only .401 bullet I had on hand. I bought a ton of these at a good price last year. I actually want to get some lead bullets for plinking. I just haven't got around to doing so yet.

  As far as primers are concerned, I have a thread here somewhere from last year. It's titled something like "800x and HST chrono results". Something along those lines anyway. And it shows my results with otherwise identical loads with the exception of primers.  I was comparing CCI #300's and Winchester WLP primers with 800x at different charge weights. The WLP primers consistently had a higher muzzle velocity of close to 40 or 50 feet per second faster than otherwise identical CCI #300 loads.

  Because of these findings, I used CCI #300's in all my test loads last night to try and lower the velocity even more. The idea being velocity is a product of pressure and therefore CCI # 300's must develop a lower pressure load than the WLP's do.  Now perhaps this was backwards thinking with my lighter loads and maybe as you stated I will get incomplete ignition by running the CCI's.

  I guess I won't know until I fire them. I'm really hoping to get an oppurtunity this weekend to give them a go. For the last two weekends it has rained and this weekends forcast looks to be no different. Of course it doesn't rain during the week when I am working and don't have time to shoot. Lol

[Dieselman]

The_Shadow do you find that work hardening tends to leave 10mm brass failing or cracking before the primer pocket looses up?  I haven't really had any split handgun brass in any caliber I have loaded. But I do junk the cases if the primer seats to easy.  Now in rifle rounds like 5.56mm, I have had split case necks prior to loose primer pockets. 

  I load a lot more rifle rounds then I do pistol rounds. What pistol rounds I do load in quantity is usually 9mm.  I haven't ever had a 9mm case ever fail. But like I said, I junk them if the primer seats too easy. Everything I load, whether it be rifle or handgun gets primed with a Lee hand primer. I never prime on my press. Not even with my progressive. I feel the Lee hand primer really gives a good amount of feedback as to how loose primer pockets are.

[DM1906]

My suggestions regarding primers was specific to Longshot and Tightgroup we were discussing. 800X is a different animal. I don't foresee an issue with your loads, only saying that if unexplained inconsistencies occur, it may be primer related with reduced loads, and that, in my experience, Tightgroup in similar charges (.357S and 9x25D, IIRC) wasn't affected either way with primer variations. It was only an observation during tests.

[Dieselman]

My suggestions regarding primers was specific to Longshot and Tightgroup we were discussing. 800X is a different animal. I don't foresee an issue with your loads, only saying that if unexplained inconsistencies occur, it may be primer related with reduced loads, and that, in my experience, Tightgroup in similar charges (.357S and 9x25D, IIRC) wasn't affected either way with primer variations. It was only an observation during tests.

Ok, thanks for the clarification.  I will report back with my findings after I test them.

[The_Shadow]

The_Shadow do you find that work hardening tends to leave 10mm brass failing or cracking before the primer pocket looses up?  I haven't really had any split handgun brass in any caliber I have loaded. But I do junk the cases if the primer seats to easy.  Now in rifle rounds like 5.56mm, I have had split case necks prior to loose primer pockets.

I have seen some split on initial firing from factory loadings especially Contract Federal 10mm for FBI/LEO (HP38/Win 231).  They use a faster burning powder and the MP-5 10mm makes them split more so than regular pistol use.

The only ones I saw primer pockets get loose for me were the Underwood 135's with 11.8 grains of 800X, primer actually popped out, bullet made 1740 fps and slightly SMILED the case even from my S&W1006.




I had some Hornady brass split on reloads testing in heavy 10mm and even 9x25 testing CFE Pistol, but attribute that to work hardening of the brass with more than one reloading.

Here was some brass after some heavy testing of 10mm...




When resizing and reworking the 10mm brass to 9x25 this can and does work harden the necks and shoulders, I have had some chips and splits about the neck and shoulder but not a complete separation as some others have had.  The sizing with respect to head spacing is crucial to the case surviving any loading for the 9x25Dillon.

[Dieselman]

Great post The_Shadow!  Thanks for your response and the pics.   

[The_Shadow]

You're welcome, we all live and learn...even at my age I'm still learning a few things!   

[Dieselman]

So does anyone else here have a favorite milder 10mm load that they want to share?

I have never used WSF or Unique before.