doublegunshop.com - home Forums General Discussion Double Rifles, Paradox Guns & Gauge Rifles @ doublegunshop.com Watson Bros 360EX double

Thank you Mike. It was a great visit with an old friend. As a plus I got to see family in Wisconsin on the way to/from, and that was special as it’s close to the year anniversary of losing Mom.

Chris,
That’s a beautiful rifle and beautiful deer. I really enjoyed you sharing the story about load development and getting the deer. It prompted me to research Watsons. Please keep us updated on the work to develop a LRN load.

Larry

CJF,
Sorry about your Mom.
Mike

Thank you Mike and Larry. It was a good trip, and great catching up with friends and family. I appreciate your kind words.

Curious if any of you with a 360EX 2.25" rifle have found it to be sensitive to case trim length.

I had a case fail with a pin prick hole near the base. I checked the length and found it to be 2.31". I wasn't sure if these had been stretching out with repeated firings. Possibly. I trimmed them all back to ~2.25" using cludged equipment (a Lee case trimmer and drill, intended for a different cartridge) and after tediously trimming 26 cases, I thought to measure new Bertram brass...which turned out to be 2.31" long.

I've had good accuracy from two rifles with the long cases, but also had inconsistent velocity. Curious if that will change after trimming.

How much is inconsistent? I wouldn't think 0.06 would make that much difference. If the cases are unequal in length by that much, I guess it's possible but doesn't seem very probable.

I read the whole thread but must have missed your load. If the case fill is short would be more suspicious of case fill than case length causing inconsistent velocities.

Having said that, it IS definitely a lovely rifle!! Congrats on the buck as well!

I'll also second everything that has been said about cast bullets.

CJF,
You might recall I asked about the rim thickness on your ammo, because I found that mine accepted 38-55 rima whereas I had to thin the same rims for 6.5x48R, 6.5x58R,
8x57R/360 and 8.25x57R Hagen. If your loads have enough of a shoulder that it is set back in sizing and the cases have thin rims, causing case stretch, your initial thought may be the cause. I suggest you smoke the neck (or ink it) of a fired case and size it just to where it "kisses" the neck and compare it to one sized as before. A pin prick hole would be more consistent with a partial head separation than excessively high pressure. You can also make a chamber cast to discover the true chamber length. It is not unusual for new cases to need trimming to length. I hope this helps, but if the cases had been fired many times the loss of one with no other damage is not especially alarming.
Mike

Sharps4590 - I'd been using mostly 21gr of 4198, without filler, but I haven't circled back to reloading for the 360EX in more than a year. Since then I've been using kapok fiber as filler in loads for my other BPE rifles (450 3.25", 500 3" and 500/450), plus a 9.3x72R. It's helped in all of those to reduce velocity variability, so I will be using it this time in the 360EX. Thank you for the compliments re the rifle and the buck.

Der Ami - I've been using the same brass in my Watson, plus an Alexander Henry single, and on rare occasions, a G.E. Lewis hammer double rifle, which I'm sure means the brass is getting worked much more than if it served a single master. Rim thickness on the Bertram brass (based on a random sampling of 3 cases from my stores), ranges from .0395" to .0410". In comparison, a sample of 3 RWS 9.3x72R cases all showed the same rim thickness of .0465". Got to love that Teutonic precision.

I think I will start segregating my 360 brass by rifle. I've already resized the cases I'm reloading so I can't try what you're suggesting right now.

On a related note, I also have a Springer single shot that was sold to me as a 9.3x57R. I've not yet cast the chamber but it does seem tighter than any of my other 360 rifles. I've tried the process I used with my Triebel-made double rifle in 9.3x72R, where I wrap the cases roughly in the middle with scotch tape before resizing, which makes them small enough to chamber. So far that's only gotten me close with the Springer, so it's time for casting.

Thanks for the help gentlemen,
Chris

I was going to mention a filler but there's often controversy about their use. I've used filler for years and my experience echos yours, they can make a good load better.

I just worked up a load for a 'new to me' J.P. Sauer drilling in 9.3 X 72R and I believe I used 33 or 34 grs. of IMR-3031 and the case fill was enought it didn't need a filler. I also haven't chronographed the load yet but it's pretty accurate.

Did you mean 9.3x72R? Transposition to x27R?