Home Forums Reloading Big Game Rifles 270 wsm, 140 AB and magpro

I’m going to work up a 270 wsm load with 140 grain accubonds and magpro. Both Nosler and Accurate have starting loads around 65.5 grains but Nosler lists 69.5 as max and Accurate shows 72.9 as max. Velocity wise they are pretty similar (3200ish). For anyone that has loaded this combo I’m wondering which one seems closer to what you see? Seems like a wide spread to have almost 3.5 grains more and about the same velocity. I’m hoping I can work up a load that’ll get me 3,150 - 3,250fps with good accuracy.

In the 270 WSM, these work very well for me.....

Nosler 140 Accubond
RL-19
Federal 215

My best grouping in my model 70, came at 70 grains magpro, pushing a 140 Accubond at 3150, 70.5 gr. Gave me 3200 FPS 1”, 5 shot grouping (almost as good as the 70 gr.).
In my rifle, I consider 70.5 a max load.

Don’t use your power but am not surprised at all with variations between manuals. In my experience, every rifle is different and responds differently. I’ve got a Tikka T3x in 270WSM with what I assume has a tight chamber and hits pressure long before hitting any listed max loads. It’s putting 140 ABs into 1/2” at just under 3200 with RL26 (I haven’t even started playing with OAL). It’s a hammer on deer:). I’d hoped to try to tweak the load further this summer but got busy....and not at all unhappy with the results).

My Nesika 270wsm likes RL26 under 130 Nosler Etips. I really like the round.

I use the 140 Accubonds and IMR 4350, not as fast, but very accurate.

Tag

My wife's cousin loads his 270WSM with 71.0gr. Magpro and 140gr. Accubonds in Winchester brass with CCI mag primers. Shoots right at 3/4", not sure about velocity. We will be out chasing elk starting Saturday. Hopefully we will have a chance to test it out!

We will have my 270 Wthby, his 270WSM and my daughter's 270 WIN. in camp this year!

Elk Country

The 270 WSM brass I have bought varies in case capacity more than any other I have worked with. This was from relatively new lots of brass so it may be more uniform now. One batch was so thick I needed to neck turn them to avoid high pressure.

I have not used Retumbo but with both R25 & R26 & 140s I get right at 3200 fos. I would work up your Retumbo loads by velocity and stop when you hit 3,200 fps even if you are not at listed max. The cartridges with a SAAMI max of 65,000 psi don't allow much wiggle room at maximum. Doesn't take much to get a spike at the higher pressures.

I just shot my first series of groups in my 24" M70 270WSM with the 140 AB and Magpro. My previous trials were with the 140 BT and first look says my rifle may shoot better with the BT. But here is what I got with Magpro and the 140 AB, .030 off the lands, with the WLRM primer:
67.5 = 3066 FPS
68.5 = 3129 FPS
69.5 = 3173 FPS
I was sensing just a bit of pressure signs and so I did not shoot the entire string of three I had loaded at 70.0 grains. But I did have one never-fired case in that bunch that I had previously measured to take a case head expansion comparison on, so I shot that single round. The case head mic'ed .5515 prior to the shot and just .5518 afterward. This is very minimal CHE in my experience. The single round clocked 3263 FPS. This is interesting as that's a 90 FPS jump for a 0.5 grain increase, whereas previously in the ladder, 1.0 grain charge increases were giving about 50 FPS velocity increases. I think this is how nature says "stop" even though the CHE isn't much at all. On the other hand, I only fired a single round at 70.0 gr Magpro, so that reading could be aberrant, but the SDs on the first three charges were 7, 15, and 9 respectively.
Hope this helps,
Rex

This sounds like a great camp and hunt. Please post any results! Best of luck,
Rex

TRexF16,

Sorry, Nothing to report. Total dud this year. We tried a new area and it was a waste of time!

Elk Country