Powder max on .270 Winchester

[entoptics]

I had no heavy bolt, case head markings, etc., on a 94 degree day today...Am I correct in thought process that as fall comes on and temps drop, this load will decrease slightly as well?

...Sound about right from your experience?

Loads should calm down as temp decreases, but there are many variables that induce higher than normal pressures. It's for sure smarter to develop high end loads in hot weather than cold.

If you're confidant in your pressure reading, and understand the consequences of "hot rod", you won't be in much danger. Running a bit over max will not result in shrapnel. There's just considerably less room for errors and/or "bad luck".

At the "toasty" levels you're describing, I'd plan to continually monitor pressure, even after I settled on a good load. Don't get complacent and load up a bunch and forget about it.

 

[Capt RB]

You may find a pressure spike if you don't anneal your brass as the neck hardens from use. Don't start there with a different brand or even lot of brass without checking to make sure the volume is the same. Even then it is better to work back up. I was referring to finding your seating depth at 59.0 then work back up in whatever increments you choose to. This way you will have a solid number for distance to the lands and charge for that combo.

 

[James Pearson]

You may find a pressure spike if you don't anneal your brass as the neck hardens from use. Don't start there with a different brand or even lot of brass without checking to make sure the volume is the same. Even then it is better to work back up. I was referring to finding your seating depth at 59.0 then work back up in whatever increments you choose to. This way you will have a solid number for distance to the lands and charge for that combo.

OK, I see what you meant. Pressures are going to change at 59gr depending on the seating depth, which may dial that load back in and would be safer than running seating depths at the 59.5gr.

I've already built loads from 59.1 to 59.4, and 3 loads at 59.5 with .005 seating depth changes. I'm gonna hold off on these and go build the loads at 59 with varied seating depths and run those first.

If the 59's tighten up with seating changes, I may back off a little more on the load and do it again.

Thanks!

 

[James Pearson]

Just got this from an information request through Hornady. I feel much better, and know that having no extreme pressure signs was for good reason.

Hornady Support commented at: 10-07-2019 01:47
Mr. Pearson,

Thank your the email. We have all the data in our 10th edition reloading manual which is the same as our 140gr SST bullets. With the data you gave me you are under our max charge of 59.9gr.

 

[John Polk]

I told you that 60 Grains of H4851 has been the "go to" load in a .270 Win. for 130 gr. bullets for 75 years. If you can use it for 140 gr. bullets good for you. You will not be disappointed.

 

[James Pearson]

Ok, here's what we ended up with today. 145gr ELD-X, Hornady brass, 59.5gr H4831, CCI 250 primers, CBTO of 2.730; 3/4 MOA @ 200 yards with ES of 8, average FPS=3018.

This was a five round test group, along with several others but not the best. Best came with CBTO of 2.745, but these won't fit into my magazine. They are about .010 too long.

I think a metal mag rather than plastic would accommodate the extra length but I'm not sure anyone makes them?

I'm stopping the work up here and going to load a large batch and run longer range work with them. I'll try to remember to post something later on and share some of that data also.

Thanks for the pointers and the company. I hope this helps someone else trying to find a good .270/145 ELDX load. And just because it worked for me, start LOW and work up to your own components potential. Safety First!

 

[James Pearson]

That was a 22" barrel Mossberg Patriot rifle with vortex optics. I'm .045 off the lands in this particular gun.

 

[John Polk]

I think a metal mag rather than plastic would accommodate the extra length but I'm not sure anyone makes them?
There are metal magazines available, but I just don't know the name of the supplier. I'm sure someone else reading this will and will let you know.

 

[James Pearson]

New update:
Shot some random distances checking the true clicks in my optics today. Using Hornady's ballistic calculator for yardages, etc... it seems pretty consistent.

Shot 100 yard zero and got 1 MOA exactly. Slightly worse than the 3/4 we thought we had.
Shot 230 yards, 2 clicks up =1.1 MOA
Shot 320 yards, 3.5 clicks up =1 MOA
Shot 430 yards, 6 clicks up =0.9 MOA

Maybe a little more tinkering, but work is going to interfere with my play time for the next several weeks so I'll just have to call it good for now. Maybe I'll work on my shooting form a little more as most of the spread was left to right with barely a breeze today at my back.

Snap caps on the patio!

 

[entoptics]

New update:
Shot 230 yards, 2 clicks up =1.1 MOA
Shot 320 yards, 3.5 clicks up =1 MOA
Shot 430 yards, 6 clicks up =0.9 MOA

I assume you mean MOA instead of clicks? Unless your scope has 1 MOA clicks or the bullet is traveling about 4000 fps...

I'd personally be pretty happy with those results. 4 groups in a row at 1 MOA is pretty good for a factory rifle.

 

[James Pearson]

I assume you mean MOA instead of clicks? Unless your scope has 1 MOA clicks or the bullet is traveling about 4000 fps...

I'd personally be pretty happy with those results. 4 groups in a row at 1 MOA is pretty good for a factory rifle.

Exactly, 1 full value or 4 clicks on my knobs!
Yeah that might get someone's blood pumping!

 

[35 Whelen]

I'm going to try IMR 7977 in my .270 Win. with 150gr. bullets. Has any one tried it and how did it do?

 

[James Pearson]

I am continuing to run load data, changed lots in the H4831 and had to make an adjustment. Now loading 48.6gr over the 145 ELDX.

Shot several yesterday and again today. Last two days I have been hanging my 10" AT-500 plate and taking my yardages to what is extreme for me. Shooting well over 500 yards using Ballistic Flight calculator and every shot I've fired have gonged the steel. Nothing like firing and then watching the round hit the target through the scope.

I now have developed a ballistic card for this rifle along with mapping out my hunting areas with yardage references. Hopefully I'm going to put it to the test in a few weeks!

Happy hunting...

 

[James Pearson]

Group at 602 yards yesterday. I'm enjoying this!