357 MAX Chrono Data

[wvrealtor]

 

Handi Rifle

6/5/2012

Sunny, 75, lw

357 MAX

Hornady XTP

180g

H110

20g

Winchester

CCI 400

AV 1940 fps

Hi 1965 fps

Low 1922 fps

ES 42.9fps

Sd 16.5fps

ES 11.8fps

1504.6 ft/lbs

This load was causing sticky extraction in my rifle. Problem is the factory 357 mag chamber is very rough. The MAX reamer did not clean up the original chamber as I had hoped. It's so rough you can see marks on the brass even with light and medium loads. With heavy loads the brass looks like I rubbed it with sand paper in several places. I've got a flex hone on order from Brownells. Once I polish the chamber I'll retest.

Later,
  Stephen

[revbc]

I would first try some JB paste on a bore mop that fits the chamber well.  Chuck it up in your cordless drill and giver a spin.

Removes a lot less metal than a hone.

Just my 2cents worth.

Bobby

[cwlongshot]

I would first try some JB paste on a bore mop that fits the chamber well.  Chuck it up in your cordless drill and giver a spin.

Removes a lot less metal than a hone.

Just my 2cents worth.

Bobby

I agree, don't use the hone!

CW

[wvrealtor]

Noted, will try the JB paste first.

Thanks,
  Stephen

[quickdtoo]

See the chamber polishing info in the FAQs. 

Tim

[tacklebury]

Data doesn't look right if AV is average velocity, it's lower than the lowest speed read and low is higher than high?  hehe

[wvrealtor]

Oops. Fixed.

Later,
  Stephen

[RPRNY]

Wow, now I see why there is so much love for the MAX. Those are pretty darn impressive numbers!

[cudatruck]

Stephen, what over all lenght were you using? Also, what primer? I'm shooting mine on a SB1 and with medium to high pressure rounds have found pierced primers with wsp. switched to federal small rifle and still got cratering, so now trying remington 7 1/2 bench rest primers.

[wvrealtor]

Used CCI small rifle for the loads above. No signs of pressure showing on the primers. Brass was virgin and I seated the 180g XTP in the top crimp groove. I did not measure OAL of the brass since it was new. I'm planing on polishing the chamber this weekend and retesting.

Later,
  Stephen

[cwlongshot]

By and large Remington SR or SR Match primers go in my maxi loads, but CCI 400 and 450 are used as well. I use 450's in my 454 loadings and these are mush higher pressure than the maxi... NO issues.

Generally speaking a cratered or pierced primer are from poor firing pin to firing pin hole fit or sharp firing pins or small PISTOL primers. Switching to a small RIFLE primer reduces both problems allot. Yes a "hot" load may produce cratered primer indentations, but if the "fit" is good you should see only get flattened primers.

CW

[mechanic]

I've switched to small rifle, even in my wheel gun with no issues.  No more pierced primers. 
 
Ben

[cwlongshot]

Used CCI small rifle for the loads above. No signs of pressure showing on the primers. Brass was virgin and I seated the 180g XTP in the top crimp groove. I did not measure OAL of the brass since it was new. I'm planing on polishing the chamber this weekend and retesting.

Later,
  Stephen

How did the barrel turn out? Have you had a chance to go shooting again?

CW