Different or Similar -Sharps .22-45 to .257 TCU

[donald duck]

I have .257 TCU barrel for my G2 Contender. Shoot only 68 grain cast bullets. Read about Sharps .25-.45 I think these must be similar but think the factory ammo would be too hot for a Contender as it is made for semi-auto rifles. Would appreciate your comments. what do you know about these two cartridges????

[mick27]

The .25-45 maintains the same shoulder as the .223, where as the .257TCU, i assume has the improved shoulder like the 6, 6.5, and 7TCU's..

[Tatume]

The Contender was chambered at the factory for 223 Remington, which is itself a high pressure cartridge (55,000 psi). The various TCU cartridges should not exceed this level.

The 25-45 Sharps has a Maximum Average Presure (MAP) of 60,000 psi. Even if the cartridge will chamber and fire (fire forming to the TCU shoulder), I recommend against it. Although the limit of the Contender is not pressure per se (bolt thrust is what people are usually concerned with), the pressure of the 25-45 Sharps is too high for the Contender (IMO).

[3leggedturtle]

The 257TCU has a 40 degree angle shoulder. mick27 is right about the shoulder angle on the 25-45 Sharps

[midnight]

To revive a 3 year old thread, I have a 23 inch Contender barrel by MGM chambered 257 TCU. Since it is nearly impossible to find dies ( CH4D told me last Monday it might be a 2 year wait), I got a set of 25-45 Sharps dies to load my fireforming loads. After firing those I will have to wait til I get a set of real 257 TCU dies to continue. Does anyone think this is a bad idea? Since I may have 2 years to search, does anyone have or know of someone who has a set of 257 TCU dies to sell? I don't want to mortgage my house to do it. CH4D's current price is a little over $100, if they had any to sell. Some where I saw Redding listed a set for $199. I may be wrong about that because I'm unable to find it again.

Bob

[midnight]

I think I may have found a way to load the fireformed 257 TCU. Since the bodys of the 6mm TCU, 6.5 TCU, 257 TCU, and 7mm TCU are the same with only the neck dia. different. I talked this idea over with Redding. 7mm TCU full length bushing dies can be had and I ordered one. Using the appropriate bushing you could size all of the TCU cases with it. The only drawback is that on all the TCU cases smaller than 7mm TCU, the very top of the shoulder would not be touched. The guy at Redding assured me that the datum line should be correct. The only way to be sure is to try it. Worst case scenario is that I can only use the die on my 7mm TCU. Seating can be done with a Vickerman 25 caliber seater. Anyone see any pitfalls here.

Bob

[skeettx]

Coming back alive
Any progress on the 257 TCU ?