1st loading of brass is great, 2nd loading stinks. Can you help?

[newmexkid]

How much neck tension do you figure? You want accuracy? Try IMR 4350 55 grs.

 

[bob4]

New cases vs Once fired? I learned almost the hard way. Fire form new cases first with a lower charge. THEN start your load work-up. I had as much as 1 gn lower difference in my 270 when I started seeing pressure signs. I'm almost sure what you experienced was pressure change.

 

[timotheius]

New cases vs Once fired? I learned almost the hard way. Fire form new cases first with a lower charge. THEN start your load work-up. I had as much as 1 gn lower difference in my 270 when I started seeing pressure signs. I'm almost sure what you experienced was pressure change.

That's good to know. Thanks for the insight. That seems to agree with what others have posted on this thread thus far. It might take me a week or two to get out to the range again to test this, but when I do I will update this thread with my results.

 

[Diamondback]

Try using 150gr bullets - Hornady higher BC and reducing H4831 charge to around 2800fps velocity zone. Better BC and less wind drift further down range. Shooting the 130's at high velocity and high pressure just burns excessive powder, kills brass, no real benefit in a 270 Win. If you want high FPS - get a 270 WSM or 7mm WSM in a 26" barrel. It will recoil more but give you the velocity.

My 270 Win rifles do 1/2" at 100yds with Hornady 150's in factory stainless barrels. I would rather have a 1/2 MOA accurate rifle, neck sizing - lower brass fatigue, lower FPS, shooting higher BC bullets. It recoils less than the WSM / Magnums and still good on energy to reach out depending on altitude. At 8000ft it will do 1500ft lbs out to 700yds.
For a non-magnum rifle, 270 Win has some legs for an older cartridge.

 

[shphtr]

FYI - 61g of 4831 (don't remember H or IMR) used to be Jack O'Connor's favorite load for 130 g for sheep hunting. It is interesting that you mention 7mmWSM for vel. I get 3275 to 3300 FPS with RL26 and 150g Barnes much to my surprise in my 7mmWSM. 3375 FPS is the middle of a very precise accuracy node in my rifle - Kimber Montana 8400 with custom 24" barrel FWIW.

 

[shphtr]

Opps! The middle of the upper accuracy node is 3275 FPS ( not 3375 FPS!)

 

[AZShooter]

This is not the usual reason for once fired brass to loose accuracy, happened to me once. I would think it is rare but possible so I am adding it to your check it list.

If the bolt face and chamber are not aligned properly with bolt face square to chamber center line, the brass will be fireformed with base canted. When the brass is used second time their will be a slight bind unless you got lucky and indexed the case in the exact position it was fired first time.

You will have to do some runout tests with a dial indicator. Perhaps you can take some once fired brass and place it in the chamber in a few different positions of rotation and feel how the bolt closes. If you find it is snug except for one position this may be the issue.

It was one of the most difficult issues to find I had ever had with a rifle. Seems there are so many rifles out there with issues we have to chase down and solve to get the accuracy we want.

Good luck and let us know what solved your problem.

 

[Deputy819]

Have you measured case capacity of new vs once fired brass? Could be some changes going on there, and you might need to adjust charge weight accordingly

+1

I just experienced this same issue with a .243. Everything was going great with the new brass (Lapua) UNTIL it was all once-fired brass. The target results of the first loading/shooting of once fired brass horrified me. I made a "modified case" from the once fired brass and compared it to the "modified case" I'd made from the new brass. Everything had gone forward by .005" in the once fired case which I'm sure upset the vld's seating preference. I'll probably have to adjust my charge weight as well as back off a little on my seating depth to accommodate the changing internals of the brass. For what it's worth...

 

[xsn10s]

I could use some help with my load work up for my Sako A-7 Roughtech chambered in .270 winchester. When I handload brand new Hornady brass, it shoots 3/4 inch groups and I am very satisfied. However, when I reload that exact same brass after it has been once-fired, groups open up to about 1.5 inches. What's going on?

I am using a bunch of brand new, unfired bulk Hornady brass, 130 grain Sierra Game King bullets, and 61.6 grains of H4831 powder. I am also using a Redding full length bushing die with a .302 bushing. I take the new brass and run the expander ball down the mouth in order to uniform it. Then, I remove the expander ball and full length size the new brass with a .302 neck bushing. (this does very little sizing on any of the brass, but I still feel like helps to keep things uniform.) I then load it and seat the bullet with a Lee seating die. Take it to the range, and get great results. Then I take the brass home, tumble it, lube it, and FL resize it with the same neck bushing, but using no expander ball at all. (I rely on the boat tail bullet to do the expanding when the bullet is seated). I load it with the same load, take it to the range, and it shoots like crap. Do you have any idea what is causing the inconsistency between the first and second loadings/firings of this brass?

A lot going on here so I'll try to simplify it as much as I can. First off I'd reduce your load like many have suggested. Since a Sierra bullet use Sierra's book loads.

Next what is different in your loading process from the first to second load? My guess is your sizing process. I think all this work towards a certain neck tension could be part of the issue.

What shell holder are you using? Make sure you use the same manufacturer shell holder as your reloading dies. Using a shell holder from a different manufacturer of your dies can make a big difference on how much you resize your brass.

What is your case length of your brass after resizing? Does your brass need trimming? I've had accuracy issues because brass was right at max length and needed trimming.

And finally are you chamfering and deburring your brass? New brass or fired new factory ammo brass usually needs a chamfer and deburr.

This is what I would do. Get a standard FL die and resize your brass. Check the case length and trim if needed, or just trim your brass to rule out case length. Chamfer and deburr. And load to book loads. A concentricity gauge would be helpful but you could roll your brass on the table and see if it wobbles too. Hope this helps.

 

[Capt RB]

Put the expander ball back in and load it again. You have way too much neck tension. If you want to see if that is the issue buy a Lee neck sizing collet die. It will give you very straight alignment and .002 neck tension. 270'S STRETCH so you will need to bump the shoulder and trim how many reloads before you need to do that will depend on how hard you push it.
60 grains is max for a 130 in just about every book out there w/H4831 Even my old hodgdon#20, 25, and 26. As well as several others. Your face is right in line with that piece of steel so be careful