New Montana Rifle Company ASR 264 win mag load problems

[spencerhenry]

i bought a brand new stainless montana rifle company american standard in 264 win mag to replace a model 70 that i had issues with accuracy.

i have only gotten started and do not have much time to load at this time of year. but, the groups i have gotten are awful.

i have been running FL sized winchester brass, WLR primers, IMR4831, and 129gr hornady bullets. the first 4 loads i ran 5 of each 57, 58, 59, and 60gr with the bullets just touching the lands. the groups were all about the same being about 2.5" horizontal and 1.5" vertical. no pressure signs with any of the loads. velocities up to just under 3100.

then i ran 3 more loads 60gr, 61gr, and 62gr. no pressure signs, and velocities up to 3200 or so. i seated this batch to .020 off the lands. the groups are not horizontal ovals, but just as bad in size.

i am looking for suggestions before i burn up a bunch more components and barrel life.

i also have a very old partial can of h870, as well as 2 20mm pulldown powders, one has a similar burn rate to the h870, the other i would have to look up. i also have IMR4350.
this rifle is for hunting deer and such, i do not want to run a dedicated target bullet, i have sierra 120's, 107's, hornady 129's, and probably a few others.

the scope was new to the old 264 so it has maybe 150 rounds on it now. it is a zeiss conquest 4.5-14 side focus. the mounts are warne.

i have wondered if it is the scope, i have not switched it out yet. i checked the action screws, base screws, ring screws, etc...
i would like to run bullets on the heavier side, i believe the twist is a 9".

 

[spencerhenry]

anyone?

 

[ShootDots]

I don't believe anyone is ignoring you.. It is just that there are few people who shoot that cartridge anymore. I had a Win. Mod. 70 in .264 Win. Mag. back in the early 70's. That was the only one I had and the only one I knew anyone had. Hopefully someone on here may have one to help you with but they are few and far between..

 

[dmoran]

You may want to try some factory ammo for a comparison, that will give you a basis to compare from.
If it shots it like crap also, I would complain to Montana Rifle Co. about the rifle itself.
Good Luck
Donovan

 

[lawman29]

Disclaimer: No personal experience. I do have a copy of Ken Waters "Pet Loads". One of the comments he makes is "After testing three different rifles of as many models in this caliber, I class the .264 magnum as one of the more difficult rounds to reload...by difficult I do not mean physically hard; rather my reference is to a greater-than-usual degree of sensitivity, necessitating the nicest sort of balancing and coordination by handloaders." So don't get discourage he too found it difficult...

Here are a couple loads he lists:

129 Hornady 76.0 H870 3.32 length CCI 250 3,170 MV Very Accurate
120 Sierra spz 76.0 H870 3.28 length CCI 250 3,349 MV Less than MOA
125 Nosler 63.0 H4831 3.33 length CCI 250 3,217 MV Most accurate full-power load

 

[Lenard]

A very good friend bought a 300 WM from Montana Rifle. This fellow is a crack shot having shot competition for years. He could not get the gun to shoot under 2". It was sent back to the company three different times and they said accuracy was up to their standards. He later traded it off and bought a gun that would have some accuracy. For what they want for their guns, they could at least put on good barrels.

 

[Jay Christopherson]

FWIW, I think Donovan (dmoran) gave you some good advice. Getting a baseline of accuracy with factory loads is probably a good place to start.

 

[fourpower]

we have 3 264win shooting at are club. they all shoot very well but we only shoot 140gr bergers they wont shoot lighter bullets very well! 2 of them like imr-4350 and one loves h-1000 but all guns like loads on the hot side. we use temp strips on barrels so we dont get to hot. barrels are doing just great. hope this helps.ps we shoot them out to 1000yds and they do very well.

 

[wboggs]

Try some Barnes TTSX and H4831 or Norma MRP. Seat at least 0.06" off rifling.
Bill

 

[Ledd Slinger]

You cant draw conclusions of poor accuracy when you have only tried one powder, one primer, and one bullet. It obviously does not like that powder. If you have other components to try...try them. Then if that doesnt work, come back and ask for help.

One thing I will say is that Winchester primers have always given the worst accuracy with any load ive ever tested them in. Just my personal experience though. Try to pick up some Federal, CCI, or Remington primers.

 

[Rustystud]

I am shooting IMR 7828 SSC/ Federal 215 GMM primers with 120 Barnes Tipped Triple Shocks, 1:8 Muller Works barrel. They are running sub .5 moa and 3,485 fps. The load shows no pressure and is considerably higher than the max listed in the book. I think IMR 7828 is the Go to powder. I just loaded 10 boxes of 300 WSM with Hybred 100 this powder may also be a good one for the .264 WIN Mag.
Nat Lambeth

 

[FryeGuy]

not sure if you are stuck on that particular bullet. I have had great success in several different rifles using Sierra 100grain HP, with H4831SC, 70.0 grains. It is a load my father in law uses in all of his 264wm. I think he has 7 or 8 different rifles in .264WM now. always sub MOA. only one of his didn't like that particular load, it likes the 120 grain bullets instead. he uses his for deer and g-hogs, or whatever else happens by. it never makes a difference. dead is dead. I did use one of mine to kill an elk. 120 sierra spt, cannot remember exact powder, as it was years ago. 300 yds and that was it. only thing I would not recommend is the 100HP on turkeys up close. in the sendero model I used to have, I tried different primers because I couldn't find magnum primers at the time. large rifle primers worked fine. once magnum primers came back around, I did a side by side comparison with them, using oehler chrono. it didn't make a difference at all. I guess if it was really cold the magnum primers would be of benefit. try the sierra accuracy loads and hunting loads in their manual. sometimes you get lucky and they work well. just a good starting point. hope this ramble helps ya.