280AI reload issues??

17ahjoe

17ahjoe

Member
Hello Members,
I had a Winchester Mod 70, control round feed, New Haven built, bought in 1993 rebarrel’d early this year to 280AI, bought 2 box’s of Nosler brass,
Nosler artwork on them but box’s different dimensions (maybe different manufacturers??), loaded first batch, first!! Shell fired blew primer,
160gn Speer GS over 56.0gns of AR2213SC ( over there H4831) after that first one all seemed ok, went hunting, shot bout 10 Deer (Sambar)
Over about a 6 mths. Time frame, Then I rekon on second loading 2 consecutive shots blew primers and Very hard bolt lift n shiny bolt and extractor signs, and this was when I shot a Deer! My gunsmith has done a few 280AI rebarrels, and I had him check out with go n no go gauges etc, all checked out ok, he said maybe hot hi pressure loads, so I dropped .5 of a gn to 55.5, test fired all seemed ok...at first, then blew another primer, he said to drop another gn. Which I will do next load.
* headspace has been checked, 010” - 015” off the lands, with free ! bolt drop, with firing pin Assam. Removed from bolt.
Rifle shoots sub Moa, with no apparent extra recoil to be concerned about.
I have only access to Nosler brass here in Australia, Hornady at present not available.
I’m after advice from other reloaders not only for this cartridge but in general, or if any other reloader has come up against these issues,
With this calibre / brass combo?
NB. 280 Rem ammo here is about $85 / 20 that’s about $115 US dollars, so I’m not doing that!!
Any ideasapprciated.
Thanks, Jay
 

Attachments

  • C917750B-A060-4456-8E3E-716DACF089B9.jpeg
    C917750B-A060-4456-8E3E-716DACF089B9.jpeg
    76.8 KB · Views: 79
  • 41E1F8C7-80E9-4C3B-BF7C-DB9EB21F05FB.jpeg
    41E1F8C7-80E9-4C3B-BF7C-DB9EB21F05FB.jpeg
    62.3 KB · Views: 71
Did you measure your brass before and after firing? I'd be checking the oval all diameter of the case body. Are you FL sizing? Could be your dies are undersized
 
Check your case neck thickness and overall fired case length. I have to neck turn cases on all of my benchrest rifles. I neck turn on most of my hunting rifles. I could have had a catastrophic failure when a gunsmith chambered a tight neck chamber for me. He failed to tell me. Good thing I already had a cut on the necks.
 
I do FLS, I check b4 and after.
I also chamber every case after FLS to ensure easy bolt drop (with bolt firing pin assembly removed).
They all seem to chamber well, the modified case I use for bullet depth is one from this chamber that has been threaded for the Hornady OAL gauge.
My next thing will be to drop powder charge to 54.5 which is starting load in most data manuals.
Reamer used has been used before on other rifles.
I will report back after next session, any other comments ideas, suggestions appreciated.
 
I'm wondering if the chamber is cut to big in diameter? If so, the case is expanding in every direction and slamming backwards when firing from the "slop" could be the issue as well. I never ran into an issue like yours unless I was loaded hot becuase my 13 year old digital RCBS scale went of the blink. The only other time was my first go at sizing the 35 Rem in my 336. I adjusted my FL sizer to far down and I had light primer strikes. I also had a few primers sitting proud. I bought a Hornady comparator and a hand held rcbs primer installer. I measured the fired case necks and bumped back 2 thousands. My flat primers that looked like they were over pressured were no more. What was causing my flattened primers imo was I bumped my case necks back to far and they were slamming backwards when firing. My buddy is shooting someone's hand loads from an estate sale. They were blowing primers like yours. I pulled a few to find out that they were loaded below minimum load data with the powder charge that was listed on the box. Also his case necks were bumped WAY back. That's why I don't shoot other peoples hand loads. Come to think of it I have blown primers on worn out brass with less than desirable primer pocket searing pressure. Almost like they could be pushed in by hand.
 
Last edited:
Hodgdon's load data shows 52.2 to 55.5 with 160 Accubonds and IMR-4831.

Cratered primers and tattoos on the case head show pressure.

A chronograph sure would be handy, you're flying blind w/o one.

Give the barrel a good scrubbing, maybe there's carbon ring build up in the throat.
 
17,

Consider running a few of these by a velocity measuring device?

Are you chambering loaded rounds also, or just the brass after it comes out of the die?

If you get the chance, run a couple set up to your current .10-.15 off the lands loads, then try a couple seated to Speers recommended COAL and see if there is a difference in velocity.

Can you please comment on why you remove the firing pin for testing? I have several M70's, and have never done that.

What primers are you using?

I am still waiting for the day i blow a primer out. I would be very unhappy, if that happened to a 2 dollar piece of brass.
 
arlaunch said:
Can you please comment on why you remove the firing pin for testing? I have several M70's, and have never done that.
Click to expand...
Removing the firing pin assembly is the best way to check brass when full length sizing.

And bullet seating & function testing loaded ammo.
 
Is your barrel the "original" 280ai spec or the newer sammi nosler spec? There is a difference and if I remember correctly, brass at newer nosler spec are not to be used in the original.
 
Goose island, fyi,
It is Nosler, latest spec and it is Nosler brass I’m using.
Alf. I chronographed it at 2780 FPS average. Which is close to the latest Nosler book specs..
Just reloaded some at 54.5gn of AR2213SC (H4831), that’s one gn. Less than my velocity test, all measured to the shoulder on Hornady gauge that cycle thru the action ok, I will check them out tomorrow.
* fyi - checked the latest price today in AUD $ for pack of 50 brass from Nosler for 280AI .....................$250.00 retail, can not afford to blow too many primers🙃
You guys over there have got no idea how we are screwed here!!! And we have a free trade agreement, load of crap!
 
Is there anyone out there reloading for the 280AI, does anyone use a Redding Body die, and is this an advantage?
After using the body die, you neck size and then seat the projectile.
Is there a specific Redding Body Die (part number to order) for the 280AI?
Sequence would be, decap die, body die, neck die then prime, load powder and seat projectile, does anyone do that?
Jay
 
Ensure your rifle chamber is completely dry patched after cleaning. Ensure your cases are completely clean of resizing lubricant. Absolutely no wet chambers and ammunition.
 
17ahjoe said:
Is there anyone out there reloading for the 280AI, does anyone use a Redding Body die, and is this an advantage?
After using the body die, you neck size and then seat the projectile.
Is there a specific Redding Body Die (part number to order) for the 280AI?
Sequence would be, decap die, body die, neck die then prime, load powder and seat projectile, does anyone do that?
Jay
Click to expand...
No advantage to a body die, it just adds another step to your loading sequence.
 


Write your reply...
Back
Top