Home Forums Hunting & Shooting Handguns 10mm Auto and AA#9, I think I have a winner here, intersting chrono results

http://castboolits.gunloads.com/showthread.php?t=154736

This guy builds great molds.... Easy HP bullets if you want to cast it that way too....

groan:
it isn't like i don't have a number of moulds, but upon seeing that i am going to have to get in on the group buy. the guy makes great moulds, have his in .45colt, and just got a set in for the old keith bullet for .41magnum. It has the cabability of throwing a solid, hollow point, and pentad hollow point.
The .45colt one is the rcbs saa 270grain, throwing to about 283grain, and in the pentad hollow point just flat nasty.
I can see this in 10mill too.

Tell you a little story about working up loads in the 10mm Mark. I used AA's older data and their starting load for 145 gr. cast bullets with their AA#2. Hornady brass, etc. I got bulged cases, again, with the starting load. The new AA data lists no loads for the 10mm with AA#2. What to guess why ?
Buffalo Bore's ammo does not follow SAAMI guidelines.
Last of all, their is no way to "work up" loads for handguns that are within SAAMI specs and get right up to that limit. Or maybe a hair over w/o problems. E

It sounds like Safariman is working up carefully, so I don't see any problems with what he is doing. If I decided to hunt deer or pigs with a 10mm I'd likely take a similar approach. Echoing what Doc said, small changes in components can change pressures in a hurry with small high pressure cartridges.

Caveats I'd include would be:

1. AA powders were at one time notorious for lot to lot variation, so changing powder lots means starting over with load development. They are now said to be better, but I'd still be likely to buy a keg at a time.

2. in a safe place, cycle loaded rounds through the action, to confirm that bullets are not setting back in feeding, which can greatly raise pressures. I use an expander plug that is only .392" diameter, so basically it only bells the case mouth, allowing tightest possible bullet fit.

3. The unlocking of a 1911 is highly influenced by the radius on the firing pin stop. For adventurous loads I'd probably order a stop with a small radius, which delays unlocking.

4. The older Hornady manual was pretty warm on 10mm loads.



the load above was 13 gr of AA#7 (Hornady's max was 13.7), under a 155 Sierra, and ran 1425 fps. I notice now they have cut the max load by a full grain.

4. Although I probably wouldn't use it for defensive use, the ramped barrel on a Kimber gives more case support.

*****

I personally was happy with 155's at 1325 fps, which beats most modern factory .357's.

Shooting a reload that exceeds factory velocity means that one is exceeding acceptable pressure limits. The 10MM is not loaded to those old velocities for a very good reason, THEY WERE TOO HIGH PRESSURE WISE. Simple as that

I see your point, but you make a blanket statement. I routinely exceed factory velocity in my .257 Roberts but it doesn't mean I am exceeding acceptable pressure limits.

I agree partially with the second part of your post though. The 10mm isn't loaded to Norma levels because they beat dammit out of Colt Deltas.

It may not be the first...but it could be. The 10mm is pretty good even when loaded to (only) book mid-loads. Is that extra 50 fps worth wrecking the handgun we've you've been posting about so much?

How do you know that you aren't exceed SAAMI spec pressure? I'd be willing to bet that you are. On the other hand even exceed SAAMI spec pressure in the 257 Bob may or may not be unsafe depending on the exact pressure, but how do you know where that pressure is without pressure testing equipment or pressure tested load data?


Comparing load for a bolt action rifle with a semi auto Delta Elite is apples to oranges

I decided it wasn't.




Travis

Rifles to pistols is an apples/oranges comparison. I was talking about SAMMI spec in one cartridge and SAMMI spec in another.

My mention of the .257 Roberts only came from dabbling with the Remington 117 RNCL which is as pedestrian as a centerfire cartridge can be, and although I cannot prove it, I believe it can be surpassed without passing the SAMMI limit.

You, of course, are correct that without pressure testing equipment, it is hard to say that the pressure is not over Spec, but it would seem that the opposite would be true as well. That is, it would be hard to say that it IS over spec absent other signs.



I'm not trying to argue, or really even dispute you, just bouncing a thought around today.

In the spirit of our discussion, I'd say "Maybe."

There are lots of factory velocities. For example:

.38 Special loads in the 158 grain RNL variety.

It is loaded by several manufacturers such as Winchester, Remington and Federal. Take the slowest of the three, and if your handload shoots faster than that, but not as fast as the fastest of the three, even without any pressure testing instruments, I'd say you are still under the SAAMI spec.

Good point's, CT. I am still trying to figure out how to change a component, like using nickel plated Starline Brass, and stay within SAAMI. On the other hand, if Starline Brass is thicker and heavier, maybe it will withstand my loads better. At least for one firing which is all I care about for this project.

Cannot usually FIND my brass out of this pistol, it throws them easily 35-35 feet or more.

Still plan to use much more pedestrian loadings for practice and plinking. If these 80 rounds now loaded up don't KABoom while using them for the one firing I am asking of them, all is good. The few my gun will see are not going to hurt it IMO.

But if you are faster than all 3 then the chance that you are over SAAMI max is highly likely and that is my point that everyone seems to keep missing. Velocity is the only gauge that an average reloaders has to based safe pressure. Does anyone remember the article that John Barnsness wrote about convetional pressure sigh ie measuring case head expansion and checking primers to predict safe pressure? One of the rifles showed no indiction of excess presure by those methods at about 80,000PSI if memory serves and the next small powder increase was not pleasant

The case is the weak link in the 10m as is slide velocity

Does your Delta throw factory loads 30 to 35 feet? Why carry a load for self protection that you do not practice with?

If brass is going 35 feet, your frame is getting beat to chit.

Load your 180's to 1250-1300 and be happy.

FACTORY loads travel that far! Those loaded at 1250 or so. I am thinking it is the mega powered dual return slide recoil springs or high quality ejectors.

Wrong.

Brass serves as a gasket, sealing the expanding gases inside the chamber. Thicker brass means the case volume is smaller, so pressures will be higher than with thinner-walled brass. This may well mean you'll exceed your chamber's pressure limits sooner.

Throwing brass 30 to 35 feet means excessive slide velocity

So now I must go rob a Kenworth and get HIS coil springs to fit into my frame?

Has to be another way to get the brass to land closer in, but this long distance brass throwing is not bothering me. Is it hurting the gun some how?

Sounds like you really need a nice Glock.... I'm picking up the majority of my brass from an 8x10 blue tarp placed only a few feet to my right

Cast my first batch of Lee 6 cavity bullets today.... Had a chance to shoot a few just before dark..... I have had real mixed luck with other Lee molds but this one looks like it is going to be a keeper......

I have what should be a life time supply of wheel weight ingots.... 1500 Starline brass..... I got a bulk order of primers in from powder valley so cost with shipping ball park 3 cents each..... Lots of powder on hand.... So ongoing expense to shoot a 10 MM about what I can buy decent .22 ammo for these days.....

Darn maybe I do need a 1911 10 MM as well.....