280 AI starting loads ?

[lawrence97]

Just had a 280 AI built and used a .313 neck and PT&G 280 AI match reamer with .188 freebore. Do any of you have any starting or good loads to use with H4831SC and Berger 180 Hybrids?

Thanks.

 

[Bigame1]

You didn't state what your rifle was built for competition or hunting? I shoot the .280 AI 26" tube
on a trued & blue printed Rem. 700 action . Since I shoot many 7mm's I opted for the 168 Berger Hunting VLD and use 63.0 grains of Retumbo , Nosler Brass & CCI mag. primers. The reason I use mag. primers is that any load with 60 grains of propellent or more needs the extra heat especially if you hunt in cold weather and with the 168 grain bullet I have enough stopping power for anything I may run into while out hunting be it Deer,Elk or Bear. I hope this info has helped you and when you find your sweet spot you'll be very happy with your results I'm sure.

 

[lawrence97]

It is an fclass rifle. Barnard action, 32" 1.25" bartlein barrel. I will use it at 800-1000 yards.

Thanks for the response.

 

[alashley]

Let me take a shot at this. The team has been using this cartridge since 1998 for LR prone.
We won the Herrick trophy in 1999 and first place Open club in 2001 or 02, plus a couple of
shootoff spaces in subsequent years.
The brass used is NORMA 280 Remington, fireformed to the 40 degree shoulder.
For 1000 yds, the load is 57.5 grains of Hodgdon 4831 SC, pushing a MOLY VLD Berger 180
approx. 2800 fps. Primer is CCI BR-2.
For 600 yds, the load is 54.5 grains IMR 4350, pushing a MOLY Sierra 168 at some unknown speed.
Same primer, same brass. The Berger 168 VLD should work with the same load as the Sierra. We do not shoot them much at 600 yds but the 180s will hammer the x-ring.
Felt recoil is equivalent to a 12 gauge shotgun.
Notice that the bullets used are MOLY COATED !! These loads are HOT !
These loads were developed for these rifles and barrel length.
Rifle used are various custom actions with Stainless Krieger 7mm 1-9 twist, #9 profile
target barrels, 28" finished length. Your brass length should not exceed 2.523. Trim to 2.515.
Brass is weight sorted.
Loads are on a Redding S Bushing neck die with a .310 bushing. Fired rounds come out of the
chamber with .314 OD. Loads are into the rifling approx .002-.003 (soft load).
I understand that hybrids are not as sensitive to seating depths as regular VLDs.
I would suggest backing off 10 percent of this powder to start with since:
1) these loads are HOT and you are shooting naked bullets,
2) you have a longer barrel and will have increased dwell time and a greater pressure increase,
3) your chamber is probably tighter which will increase pressure,
4) again, these loads are HOT. The trace is about 4' over the target frame at 1000 yds. Start looking
for a new barrel at 2700 rounds.
These are beefy barrels shooting heavy loads. The rifle total weight may exceed the F-TR limit,
but not F-O.
I hope this is helpful.
Alan Lashley

 

[lawrence97]

Alan, thanks for the info. Was just looking for a start point and you gave me that. I intend to push the 180's out of my 32" barrel at 2950-3000 and hopefully find a compromise of accuracy and speed. If not I will drop down to the 2900 range and shoot at same velocity as my 284 and use it as my backup.
I have heard of several use magnum primers and h1000 and retumbo but I have H4831sc and large rifle primers so hopefully that will work out! Hoping for 284 shehane velocities.

 

[expiper]

Larry,,,,you got good advice from Alan,,, I use 57.5 4831-sc also,,with 180 bullets (ws-2 coated),,,,my 7-07 is a 280 AI body with a short neck( chamber length 2.500" and trim 2.480) using commonly available 30-06 brass ( WW and Lapua ),,,,,Roger