20 tcm
 

So I have been itching for a 20 TCM since I saw the cases for the first time, and have been bugging NorCalMikie about his since he let out he was working on one. Mine is on a Wasatch Precision single shot action with a Pac-Nor 3 groove 7 twist barrel.

The first time I had it out I loaded some test loads with CFE-BLK and it shot just ok and there was soot on the shoulders so I annealed the brass and loaded up some more loads with CFE-BLK and 24gr NTX bullets, got up to 13.4 grains whci gave velocities near 3300 avg, but still over inch groups. I was at a friends house and ended up using his press so I have to play around with the dies to get similar settings without having to reset them again when I got home. I had already cased up the rifle, but decided to load up 3 each of 2 different loads of N120 and LT-30 and was pleasantly surprised. The reason for the vertical you can see in the Chrono numbers, the horizontal is from fighting the wind. The CFE BLK may need more neck tension or it may be sensitive to the capacity changes of the cases as well. At this point I will take accuracy over velocity and will stick to testing N120 ant LT-30.The bottom right group is .508 outside dimensions so I am pretty happy.


http://www.saubier.com/forum/picture...pictureid=1436



when I got home I weight sorted the remaining unfired formed cases into .5 grain lots, and will use the 65 cases in the 73.1-73.5 group to test again hoping to cut down any capacity difference

there is a significant variance :
http://www.saubier.com/forum/picture...pictureid=1437


going to do these thing in retests to try and improve:

• compare pistol vs rifle primers
• use my chargemaster to measure the loads
• use the weight sorted brass

:cool::cool: Love to see a picture that Wasatch Precision single shot rifle. Nothing like that on their site. They show a killer 10/22 for $700.00 +.:eek:
Never paid that much attention to FPS. A 5 shot group @ 100 yards that I could cover with a dime ALWAYS brings a smile to my face.;)

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Never paid that much attention to FPS. A 5 shot group @ 100 yards that I could cover with a dime ALWAYS brings a smile to my face.;)[/quote]

I am with you on that Mikie.. :D Accuracy trumps FPS every time. Bill K :)

I will get a picture of the rifle up later. As you might imagine trying to take a rifle outdoors to take pictures in an apartment complex in the communist territory of CA might cause an uproar.

Did somebody say GUN???:eek::eek:;)

I really can't address the .20 TCM because I don't have one, BUT -- in the .22 TCM the only powder I could get to really shine was LilGun, and the accuracy node with everything I tried, including LilGun, was tiny. Jus' sayin'.

NorCalMikie look here
 

I think once I get my brass and dies squared away that N120 and or LT30 are going to shoot small. I have to grin -in Ackleys books, I think for 17 Bee he describes filling the case to the top scraping it off and seating a bullet, this is pretty close.

One of the challenges in this project was getting bullets seated until I was ready to order dies, and I had the neck area of a Hornady 20 cal seater opened up to just over .237 because these little cases have thick necks. I figured out last night that the seater being finicky is mostly due to the fact some of the neck are close or over that dimension. It took crushing a couple of cases to wake me up. I will end up skim turning my cases to make sure they stay under the .237 and have clearance for the neck which is .239. Thinking that rather than my powder throwing might be responsible for some of the spikes in the chrono numbers.

http://www.accuratepowder.com/produc...25&product=TCM

Does it not work worth a darned in the cartridge it was marketed for?

TCM powder
 

I actually sent them a question about that and the answer I got back was LT30 would probably work better - In his opinion the TCM powder was too fast for the regular TCM in a pistol even:rolleyes: People who have been around here for a while will recognize the name Rob Behr, he does the load development and testing for western powder.
Drew

Could it be that that Accurate Arms Powder might work better in a "rifle" over the short barrel of a pistol?
Accurate Arms is the only powder I use in my rifles and have never had issues.