Ruger M77 MK2 in 260 remington

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ive been daunted with the task to work a load for a friends ruger m77 .260 caliber rifle. he provided me with RL.19 RL.22 new Remington brass. CCI 200 primers, a set of dies and Hornady 129 gr. SST bullets.

1st set of tests. I ran a OCW with the RL19 set to the specs of the Hornady reloading book. and with shells full length resized, cases trimmed to consistant length below max ( im not too sure of the exact measuring ill have to look at my notes) primer pressed in on the press (CCI 200's) 3 bullet OCW, again I don't remember the numbers ill have to observe my notes. with consistant seating verified with optical comparator. when shot from a shooting rest and sandbags from a solid bench, the targets looked as if they were hit with buckshot. I went back to my reloading bench and tried putting a roll crimp on the bullets cannelure to see if a difference was made. which there was no difference.

2nd test was done with RL22 to the same exact specs as the 1st set. I started getting groups. not great ones but 3" or less. starting at 45.5 gr. and they were all sporadic until I hit 47 grains. right at a 1 inch group with 3 shots. this is awesome. until I go home and try to tune seating depth.

with now, once fired brass, I tumble clean and resize the formed brass again. i set the bullet out 0.01" and set it deeper 0.005', and 0.01" I only went this far so that a crimp will still sit on the cannelure. to my disappointment my groups opened back up to about 3 inches.

so here I sit. trying to figure out where to go from here. I feel that just by moving the seating depth that much shouldn't have mutilated my groups like that.
the owner of the gun told me that 120 grain ballistic tip bullets are tac drivers in it. but he wanted a heavier bullet for long range hunting.
does anyone have a load with this particular bullet and this rifle I can try?
im a novice reloader learning from reading and watching videos and I could be overlooking things that make a huge difference in accuracy. I try to be very consistent and thorough with my notes.

and help, assistance, insight or correction are welcome.
 
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I had the Ruger Compact MkII in 260. I shot it with 100 and 120 gr Nosler BT's. I used a warm load of IMR4064 with the 100's and warm load of R17 with the 120's. It shot great.

For 140's, go straight to H4350. That is what you want. Tried and true. That said, having used the 120's on deer and pigs, that's all the bullet you need. For long range paper or steel shooting, the 140's are better.

Start out, using the 4350, at factory COAL and see how it goes.

Ya gotta trust me on the H4350.
 
thanks for the reply. ive been reading on other forums and such about H4350 but I wasn't sure if it was tried and true, or just someone got lucky with their gun. I have IMR 4064 sitting on the shelf but Ill run to the local Cabelas and pick up some H4350. with the 1:8 are 129 SST's stable enough for that gun?
 
Hi. The Trim-to for a .260 Rem is is max. Tolerance, according to SAAMI, is -.020" vs the .010" Hodgdon gives. Lot of wiggle room. The 'consistent' part is more important anyway. As long as it's between the 2.025" and 2.035", it'll do. Just don't forget to chamfer and deburr. Makes bullet seating a lot easier.
The ladder test really doesn't tell you anything about the accuracy of a particular load. Just tells you where the bullet hits in relation to other loads. Another thing that'll do though.
Forget the cannelure altogether. OAL for a 130 is 2.780". Save you a lot of mucking around to seat to that length.
Wouldn't bother with the 'off the lands' stuff until I had a load either. The 'off the lands' thing is a load tweaking technique that may or may not be necessary. Lotta trial and error with it too.
"...until I go home and..." Rule Number One. It works, quit fixing it. An M77 is a hunting rifle, not a target rifle.
 
sorry you found a mistake in my original post. I didn't do a ladder test I did an OCW test. 3 bullet groups stepping up half a grain at a time. I know the ladder test is pointless at 100 yards.. tried that too with no luck. but what your saying is that I need to seat the bullets to 2.780 and don't worry about crimping and ignore the cannelure.
 
the owner of the gun told me that 120 grain ballistic tip bullets are tac drivers in it.
Click to expand...

Have you witnessed this and seen it done on a consistent bases with that rifle? I only ask because some people tend to overstate rifle accuracy and when put the test off a bench all of the sudden the gun does not shoot nearly as well as was stated.
 
no I have not seen it, but, I do have said ammunition attached in a holder sleeve on the stock. so today when I go shoot. I will group them for myself.
 
My newer 260 is an extremely accurate Tikka. It loves both 100 and 120 gr Nosler BT's. Shoots them to the same POI also. Recent 5 shot group with R17 gave me a ragged one-holer. Note that many hunting magazines use the Ballistic Tips for accuracy tests. I doubt that's a coincidence.

That said, I get excellent accuracy from Sierra Gamekings and Hornady SST's also. But primarily, due to decades of happy use, I am a Nosler BT fan.
 
For me the SST's like to be seated about 0.015" off of the lands. Also, Alliant usually lists Federal Primers for their data.

Plenty of room in the magazine of the 77 to seat bullets long.

603,
If you like the 4350's then you would love RL17. Close to same relative burn rate, but higher velocities.
 
Std7, note that I mentioned that R17 is what I use behind the 120's. I bought it in the hopes that I could wring a bit more MV out of the 16.5 inch barrel on the Ruger Compact. It worked so well that I just stayed with it when I got the Tikka. Only issue with the R17 is temp stability, a problem that H4350 does not have. And even though some folks have an issue with the temp stability of R17, I did notice that my new bottle of powder had verbiage that said R17 was stable in extreme temps. The old bottle didn't say that. Anyway, I get such great shooting with the R17, and don't hunt in temp extremes, that I'll just stay with it.

So, H4350 is probably the best choice of 260 powders if you are a year round target shooter, but R17 is still a good choice for hunters. It sure works for me, being mostly a hunter, but still an informal paper puncher.
 
I was curious as to why you swore by H4350 but in your own loads you stated RL17. thanks for clearing that up. I wasn't able to get to the bench yesterday. hopefully today proves better.
 
The first thing to do, in my opinion, is a thorough cleaning of the gun with an excellent copper remover. Alternate between an excellent remover and one that turns purple. Most of the color changing ones are crappy cleaners but good at telling you copper is still there. Repeat until no more purple.

The second thing to do is check the torque on the action screws.

The third thing to do is shoot that factory ammo. It might not shoot "great" with any given ammo but you should be able to get groups.
 
So I acquired some h4350 and none of my books specify load range for 129 gr. SST? Anyone offer me some assistance? With federal 210 primers
 
Thank you! Was just sitting at my reloading bench when you replied. I thoroughly cleaned the gun and retorqued the action screws. They were somewhat snug. But I gave them another half turn in
 
To be clear, my concern with the action screws is that the are *TOO* tight, not too loose. Some guns (and in my experience MANY M77 MkII) are rather picky about action screw torque.

The M77 action sits in the stock at an angle. Ruger specifies 95 in-lbs for the front screw and I've read anything from 50 to 95 for the rear action screw. (The 3rd one just holds the trigger gaurd, it doesn't matter).

However, it is indisputable that action screw torque is very much the same as cartidge OAL and a thousand other variables.... not all guns like the same. You'll have to experiment.

I'd start around 30 in-lbs and go up in 5lb increments until you get good groups and/or you can tell if there are significant changes.
 
thank you for bringing this to my attention. i will torque them to those specifications as soon as i get home. i wasn't aware that action torque played that big of role in accuracy when it comes to these rifles. i knew this barrel wasn't free floated and no bedding was installed but i wasn't aware that these screws had that much affect on accuracy.
 
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I tested the H4350 with federal 210 primers. 4 groups 3 loads each. 40 gr-43 gr. Best group I got with letting the barrel cool was 1.25" that was at 43 gr. I started with 40 gr. Group was right at 1.5 but two of the holes were about .3" apart with my first shot being the one further from the other two. The second and third groups expanded pretty bad. 42 grains being about a 3" group. I'm starting to think the stock is getting heat soaked and causing the barrel to have pressure in areas it shouldn't. The last group I shot was 3 rounds of the factory tack drivers which produced a 2.5" group with a warned barrel. I talked with the owner of the gun who informed me that he put 5 rounds of factory in a quarter sized group with holes touching. So what should I do? I don't think my aim is that bad. Again shooting from a solid bench off sandbags. I'm at my wits end btw I retorqued the action bolts back to factory. Could it be the scope. I have the targets. Would pictures help?
 
Well, I'd ask the previous owner what his favorite load was. And when you bought the rifle, did you buy his scope, or did you use something else? If he can shoot tiny groups with the rifle, something has changed. Could be the scope. Could be user error. :-)

Other than that, I'll mention that I also got good groups with IMR4064.
 
A bad scope would normally cause random shot dispersal but random is hard to tell with only 3 shots. When you're shooting that poorly the scope has to always be suspect. I'd drop another one on there that's known to be good. Doesn't have to be a Nightforce, just has to shoot groups.

It's unlikely to be the stock but it should be checked. Normally, it should only be touching at the forend where Ruger puts a pressure point. The rest should be free floating back to the action "pillar". Try to slip a dollar bill in between the stock and barrel and see if you can run it cleanly up and down all the way from the front action screw pillar to the forend pressure point. Any spot where it drags is too tight and should be sanded out.

Also, I obviously don't know the owner but I'm always suspicious of such claims of group sizes. A quarter is under 1" in diameter. He's talking about 5 shot groups barely bigger than 2/3". That would be... remarkable... to say the least. Maybe he did it once but I highly doubt it was repeatable.

Finally, I realize that it doesn't matter if you're getting 2.5" groups but your charge increments are too large for proper OCW tests. Dan Newberry (the OCW creator) recommends increments of 0.7-1% of maximum charge weight. In this case, that would mean no more than 0.4gr and 0.3 would be better.
 
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