270 Weatherby Mag load data

R

Rex Rugged

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Does anybody have any suggestions for the 145 SH in a 270 Weatherby Mag? I have looked for info on where to start my ladder and cannot find any. I have H4350, IMR4350, RL22, N560, N160 on hand. I thought I would give them a look/see since they are recommended for the 1-10 twist. I that I found interesting.
 
I’d use Nosler or Barnes online data for 150gn bullets as starting point. Looks like 62 to 64 gns start, depending on the powder.
 
Start with the N560.

Should give the most complete fill and the most velocity.

I'm not qualified to give reloading advice, but if it were me I'd start at 66gr and load up to 72gr.

I've loaded the 133SH's in the Weatherby, RL26 gave great results. Started at 68gr and it was a long ladder - didn't found pressure until 80gr!
 
OK so I loaded my Cartridge's with N560 starting with 64. grs and increased in .5 grs through 67.5 grs. I have concerns about neck tension that I will address later with a mandrel or neck die. So I gave each cartridge a very slight crimp. The OAL was an extreme of 3.344 when compared to Sierra's recommendation of 3.295 but they chamber up easily so I assume the base to bullet ogive is suitable. I hope to go to the range tomorrow alternating two rifles between 3-shot groups. I will shoot 1 minute apart and hope this will keep the barrels cool enough to not widen the grouping much. I will come back here and give results. Oh and I do plan on taking a chronograph.
 
Great suggestion, @gltaylor

In the interest of safety, I view this as a requirement, not 'optional'.

Should be lots of freebore if it's a Weatherby, but very important to check before loading a new bullet.

Just because the overall length is good doesn't mean the bullet isn't jammed when chambered.

This is especially important with Sledge Hammers, which have an ogive closer to the tip (or hollow point in this case)

@BFD introduced us to a great method for finding the lands;

Gravity Method: Finding Distance-to-Lands (DTL)

Tool-less method for finding bullet distance-to-lands (DTL) 1. Clean chamber/throat. 2. Muzzle to sky with buttstock on bench. 3. Load a newly sized brass into the chamber with your pinky finger. Press hard on the back of the case head. It should fall by gravity after release. - This is a...
hammerbullets.com
 
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gltaylor said:
Please verify your clearance (jump) to the lands. A jump of 0.020 is recommended for starters. Less jump can lead to premature pressure.....
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I took your advice and checked the jump as best as I could made an adjustment and feel better that I did. I actually had too much jump! They still chamber easily but are .02 closer to the lands. Weatherby has a great deal of free-bore on their 1-10 twist rifle I guess. Thanks for your heads up. LOL Just saw your post Hand skills printed out your method, thank you very much.
 
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So today at the range I sent 3 shot groups of 145 SH's starting with 64 grs of N560 in .5gr increments to the top of the ladder at 67.5 grs. Best group was a tight cloverleaf by 66.5 grs. Two groups, 66 grs and 67.5 grs were spread to 1 1/2" 4 groups were two shots within 5/8" an inch but had 1 flyer out to 1 7/8" Don't think I was pulling that much but I'm sure I pulled some. Got to find out what causing that. Still I think there is a lot of promise from my first experience with these heavier bullets. They sure are long!

I also just tapped a shell to fit on my Stoney point gauge and discovered I was within .035 of the lands. Will play with that measurement. Another interesting hurdle was the bullet did not want to load like it should. The point was hitting something maybe the shoulder and stopping cold. If I jostled it with my finger it would then easily slide into the chamber. Maybe the weight and length of the cartridge is making the nose drop causing this. Strange.

Oh one more thing, No sign of pressure. Sides of primers are shiny and just a very slight ridge ( can just feel it with fingernail) where the pin struck.
 
If you have room in your case, don't be afraid of jumping a Lot more. Shortening your case may improve your case geometry and allow better feeding. Hammers don't mind jumping. Some of my loads jump as much as 0.150+ and they do very well🙂! Increase your jumps in increments of 20 thousandths and watch your groups.
Weatherbys are like RUMs. HUGE freebore.
 
So I went to the range to continue working up the ladder, 68-71.5 grs of N560. This time I didn't forget my Caldwell chrono. Starting with 68.grains of N560 produced a 1 7/8" group at 2559FPS. The next group at 68.5 grs was much better group at 15/16ths but the bothersome thing was the velocity rose to 3289 FPS. I wondered if the Chrono was working correctly. It did slowly increase as I worked up the ladder till the last group was sent at 3388 FPS! That is sending a 145 grs of copper pretty darn fast! The best node of the day was 70.5 grs that was a dandy 5/8" near cloverleaf travelling at 3361 FPS.

When I got back home I de-capped the primers and found shiny primers until 70. grs and then they were no longer shiny and appeared to be on the verge of leaking. Very slight ring around the firing pin crater. Inspection of the Norma brass showed no swipe signs but reflected light under a magnifying glass a circle appeared with a very, very light line around them. I checked and determined this was a bit of imprint of the ejector pin hole. I had no issues with bolt lift. No swipe marks. My thinking as of right now is to dial in at 70.5 grs and see if I can shoot for consistent accuracy.

Any thoughts from you guys. This is 145 SH at 3360. Would that be a good elk load to work with within 400 yds or should I dial back to the 122 grs Hammer Hunter? I know there is no firm answer with so many variables but I do not underestimate the value of experience.
 
Rex Rugged said:
Any thoughts from you guys. This is 145 SH at 3360. Would that be a good elk load to work with within 400 yds or should I dial back to the 122 grs Hammer Hunter? I know there is no firm answer with so many variables but I do not underestimate the value of experience.
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Great work, be sure to test your load on a hot day to ensure pressures remain safe for any condition you might hunt in, then Happy Hunting!!
 
The 131 HH at over 3300 went front to rear on a whitetail buck at 360 yds in my RUM. I should think you're good!!!
Bullet entered at chest/brisket and shank was recovered under hide at rump😀
X"s 2 on testing at warmer temps.
 
Schmo said:
@Rex Rugged,
You can also evaluate where you’re at on pressure by measuring primer pockets.
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I'm using a go-no-go from Ballistic Tools and tossed about four of the hundred or so Hornady cases, the Norma cases are once-fired so all in good shape. Still I guess I could measure to see what I can determine to be expanded pockets.
 
One of the interesting aspects of Hammers is losing the cup and core heavy bullet kills better thought concepts.

The 122HHT is going to be a laser as well as the 117HH which has been proven out on everything including elk. The 117HH has proven to be very accurate as well. The 122HHT is also right there.

The 117HH is also an exceptional bullet in 277 calibers. Take a look at the load data for .270 Win just to see the velocities being run with it.

I am betting you can drive it to pretty interesting velocities in the .270Wby.
 
Muddyboots said:
One of the interesting aspects of Hammers is losing the cup and core heavy bullet kills better thought concepts.

The 122HHT is going to be a laser as well as the 117HH which has been proven out on everything including elk. The 117HH has proven to be very accurate as well. The 122HHT is also right there.

The 117HH is also an exceptional bullet in 277 calibers. Take a look at the load data for .270 Win just to see the velocities being run with it.

I am betting you can drive it to pretty interesting velocities in the .270Wby.
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OK I will start a ladder for the 122's I have and collect the data. You are on point with my thought process. I just have to accept on faith that the lighter bullets kill as effectively.
 
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