25x45 or 25/223

[320pf]

I had a chance to try loading(W748 in the 25-223AR*
*.223 parent brass opened up to .25-cal; shortened to 43mm; maintains .223 body taper, same body shoulder junction height, does't require fire-forming.


Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow) Note: The powder was loaded into the case using an eight drop tube. This facilitated a more dense/compact powder column.

100 gr Speer SPBT (16-inch barrel)

25.5gr W748 = 2350 fps
26.0gr W748 = 2411 fps
26.5gr W748 = 2435 fps
27.0gr W748 = 2475 fps
27.5gr W748 = 2510 fps
28.5gr W748 = 2548 fps

No signs of high pressure. Am interesting phenomena occurred with this load. The ejected brass was was cool to the touch. The barrel was was only mildly warm after each five shot string. SO this powder must burn pretty cool. There was NO powder residue in the barrel after each shot so W748 must also burn fairly clean. In addition, all 30 round from this test grouped within 3-inches over the 200 fps velocity spread. I was not trying to shoot for groups.


I used the published loads for BL-C(2) in the 6x45mm found the Hodgdon reloading manual for a starting reference. The Hodgdon web site shows that W748 is ranked at 82 and Hodgdon BL-C(2) is ranked at 83 on their burn rate chart.

For example Hodgdon lists:

6x45mm
85 gr SPR SP BL-C(2) (24" barrel)
Start: 25.5gr.-2566 fps; Max: 27.5gr.-2811 fps

90 gr SPR SP BL-C(2) (24" barrel)
Start: 25.05gr.-2523 fps; Max: 27.0gr.-2744 fps

100 gr HDY SP BL-C(2) (24" barrel)
Start: 24.5gr.-2404 fps; Max: 26.5gr.-2619 fps

320pf

Originally Posted by 320pf

Well I finally got my 6.35.43mm (257/223) project together. Here are some early results:

Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow)

100 gr Speer SPBT (16 inch 1:10 twist barrel)

23.0gr H4895 = 2294 fps
23.5gr H4895 = 2336 fps
24.0gr H4895 = 2350 fps
24.5gr H4895 = 2400 fps
25.0gr H4895 = 2463 fps
25.5gr H4895 = 2505 fps

75 gr Hornaday V-Max (16 inch 1:10 twist barrel

25.5gr H4895 = 2560 fps
26.0gr H4895 = 2600 fps
26.5gr H4895 = 2678 fps
27.0gr H4895 = 2728 fps
27.5gr H4895 = 2803 fps

I think that H4895 is a bit too slow of a powder for this cartridge. Also there is no way that I can get anything close to the amount of powder in this cartridge as that listed for the 257 Kimber. I have some IMR 3031 around to try but from the data posted by Kurtz on his 25/40mm I think that 1680 may be the best powder.

We will find out.


320pf

[320pf]

UPDATE: 6.35.43mm (257/223) project

I am running the gun with the gas port turned off to see how it runs before I the port in. Here are some new results.

Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow)

75 gr Hornaday V-Max (16-inch barrel)
for starting load reduce powder charge by 5%
21.9gr IMR4227 = 3020 fps
Primers were round and brass look good.

87 gr Speer TNT (16-inch barrel)
for starting load reduce powder charge by 5%
21.9gr IMR4227 = 2840 fps
Primers just starting to flatten edges and brass look good. For my rifle, I would reduce this load by 0.2 to 0.5gr for general use.

These results seem to confirm that H4895 and W748 powders are too slow for this caliber at this barrel length.

320pf

Originally Posted by 320pf

I had a chance to try loading(W748 in the 25-223AR*
*.223 parent brass opened up to .25-cal; shortened to 43mm; maintains .223 body taper, same body shoulder junction height, does't require fire-forming.


Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow) Note: The powder was loaded into the case using an eight drop tube. This facilitated a more dense/compact powder column.

100 gr Speer SPBT (16-inch barrel)

25.5gr W748 = 2350 fps
26.0gr W748 = 2411 fps
26.5gr W748 = 2435 fps
27.0gr W748 = 2475 fps
27.5gr W748 = 2510 fps
28.5gr W748 = 2548 fps

No signs of high pressure. Am interesting phenomena occurred with this load. The ejected brass was was cool to the touch. The barrel was was only mildly warm after each five shot string. SO this powder must burn pretty cool. There was NO powder residue in the barrel after each shot so W748 must also burn fairly clean. In addition, all 30 round from this test grouped within 3-inches over the 200 fps velocity spread. I was not trying to shoot for groups.


I used the published loads for BL-C(2) in the 6x45mm found the Hodgdon reloading manual for a starting reference. The Hodgdon web site shows that W748 is ranked at 82 and Hodgdon BL-C(2) is ranked at 83 on their burn rate chart.

For example Hodgdon lists:

6x45mm
85 gr SPR SP BL-C(2) (24" barrel)
Start: 25.5gr.-2566 fps; Max: 27.5gr.-2811 fps

90 gr SPR SP BL-C(2) (24" barrel)
Start: 25.05gr.-2523 fps; Max: 27.0gr.-2744 fps

100 gr HDY SP BL-C(2) (24" barrel)
Start: 24.5gr.-2404 fps; Max: 26.5gr.-2619 fps

320pf

[320pf]

I have more load data for this wildcat.

I am running the gun with the gas port turned off to see how it runs before I the port in. Here are some new results.

Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow)

IMR4198 Speer 87g Hot-Cor Spitzer SP
Load =vel (fps)
20.0 2495
20.5 2531
21.0 2585
21.5 2663
22.0 2704

The Powley pressure calculator (found here: http://kwk.us/powley.html) indicates that the 22.0 g load is generating about 50000 CUP. One might be able to get another 50 fps out of this load.

320pf

Originally Posted by 320pf

UPDATE: 6.35.43mm (257/223) project

I am running the gun with the gas port turned off to see how it runs before I the port in. Here are some new results.

Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow)

75 gr Hornaday V-Max (16-inch barrel)
for starting load reduce powder charge by 5%
21.9gr IMR4227 = 3020 fps
Primers were round and brass look good.

87 gr Speer TNT (16-inch barrel)
for starting load reduce powder charge by 5%
21.9gr IMR4227 = 2840 fps
Primers just starting to flatten edges and brass look good. For my rifle, I would reduce this load by 0.2 to 0.5gr for general use.

These results seem to confirm that H4895 and W748 powders are too slow for this caliber at this barrel length.

320pf

[Bigfoot]

Nice work.

I bought a SU-16A last year, the barrel screws in and headspaces like a Savage. So with just the purchase of a barrel I could take this 5lb rifle blacktail hunting. 80 gr TTSX at 2900 or better?

Thanks for sharing.

[320pf]

Originally Posted by Bigfoot

Nice work.

I bought a SU-16A last year, the barrel screws in and headspaces like a Savage. So with just the purchase of a barrel I could take this 5lb rifle blacktail hunting. 80 gr TTSX at 2900 or better?

Thanks for sharing.

I am not exactly sure how the SU-16A barrel attaches and headspaces. However, I can tell you that the 25-223 uses standard 223 REM/5.56 NATO headspace gauges and a standard 223 REM/5.56 NATO bolt. So I would think that a 25-223 barrel should work just the the 223 REM/5.56 NATO barrel that comes with the SU-16A

I hope this helps

320pf

[320pf]

A few folks are getting early Xmas presents. Here are the three main barrel lengths that people are going with in this wildcat cartridge, 16, 18, and 20 inch. I hope we will see some range results with the next month or so.

320pf

[VaFish]

Sorry for the crappy cell phone pic,

But here is what the 16" barrel looks like installed:
http://i109.photobucket.com/albums/n...-10_222308.jpg

My first quarterbore rifle!!!

Now if my reloading components would get here.





Edit by mod to resize big pic

[SgtCottle]

I like the silver trigger look ... who makes it?

[VaFish]

Originally Posted by SgtCottle

I like the silver trigger look ... who makes it?

It's a stainless steel fire control group. Got it a while back I think I ordered it through R-Guns.

[320pf]

Here is more load data for the 25-223Ar. I had a chance to try Hodgdon H335 today. It seems to be the best powder I have tried so far.

Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow)

Hodgdon H335, Speer 100 gr SPBT (16 inch 1:10 twist barrel)
Charge
wt.(g)-------vel. (fps)
24.8---------2460
25.7---------2560
25.9---------2581
26.1---------2604
26.5---------2624

I hope this helps

320pf

Originally Posted by 320pf

I have more load data for this wildcat.

I am running the gun with the gas port turned off to see how it runs before I the port in. Here are some new results.

Load Data: (standard disclaimer as with any wild-cat, use at own risk and work up slow)

IMR4198 Speer 87g Hot-Cor Spitzer SP
Load =vel (fps)
20.0--2495
20.5--2531
21.0--2585
21.5--2663
22.0--2704

The Powley pressure calculator (found here: http://kwk.us/powley.html) indicates that the 22.0 g load is generating about 50000 CUP. One might be able to get another 50 fps out of this load.

320pf