260 Load Development

[slas]

I've started reloading for my Tikka 260 and was hoping to get some input on what others are doing. It's got a 1:8 twist on it so I know it should shoot the 140 grainers well but I wanted to start with 120 and 130 grain first thinking one of them would be my OK deer load. Last week I loaded some 120 grain Sierra Pro Hunter's but most of that was for break in. Last week I picked up some Berger 130 VLD Hunting bullets and loaded them up. Below are the results of my first attempt with these bullets.

IMR 4451
41g - 2541
41.5g - 2581
42g - 2585

Varget
36g - 2556
36.5g - 2606
37g - 2653

IMR 4350
42g - 2621
42.5g - 2621

The OAL was set to 2.960 with a few groups set at 2.965 (distance to my lands is 2.980). My research on the web showed most had success .015 to .020 off the lands. All the above speeds are considered low so I'll need to work up while checking for any pressure signs. Had none with the groups above. Groups were fair with the IMR 4451 showing good accuracy albeit the slow speed. I've had trouble finding H4350 so looks like I'll be trying to find the sweet spot with one of the above powers, leaning more towards the 4451 right now.

Please share your pet loads,recipes or advice.

 

[swampratt]

New gun and different powders.
I take it to 200 yards and do a ladder test in the velocity range that makes you happy.
I usually start just a tick above the start load and with your deal I would step up in .4gr increments.
Shoo t at 200 yards and see which loads were closest together.. then work in that range of powder charge playing with seating depth and type of primers to really hone in on the perfect load.

I also found when searching for the perfect load I need to anneal my cases each time.
I leave the chrony at home when working up a load.. it can be misleading.

I have had loads that were withing 3 fps of each other and they shot like crap lucky to hit 8" at 200 yards.. then other loads that were 25 fps apart but shot under 1" at 200 yards.
Give the gun what it wants.
100 yard shooting hows me nothing.. many of my good loads shoot 3/4" at 100 but hold that same 3/4" group at 200 also.
Odd how things happen sometimes.

 

[slas]

New gun and different powders.
I take it to 200 yards and do a ladder test in the velocity range that makes you happy.
I usually start just a tick above the start load and with your deal I would step up in .4gr increments.
Shoo t at 200 yards and see which loads were closest together.. then work in that range of powder charge playing with seating depth and type of primers to really hone in on the perfect load.

I also found when searching for the perfect load I need to anneal my cases each time.
I leave the chrony at home when working up a load.. it can be misleading.

I have had loads that were withing 3 fps of each other and they shot like crap lucky to hit 8" at 200 yards.. then other loads that were 25 fps apart but shot under 1" at 200 yards.
Give the gun what it wants.
100 yard shooting hows me nothing.. many of my good loads shoot 3/4" at 100 but hold that same 3/4" group at 200 also.
Odd how things happen sometimes.

Do you anneal if you'll only be neck sizing? Or do you anneal and do a full resize each time? I'll only be shooting out of one rifle so I figured I'd neck size only a few times before doing a full resize. I found I can usually neck size about 4 times before the cartridge starts feeling sticky, then I will anneal and do a full resize and start the process again. Curious how others do it.

 

[swampratt]

Think deeply about what you just said.
Or think deeply about what is happening during neck sizing only and firing then Full length sizing.

Not 1 time in 5 shots is your brass the same dimensions. Each time you neck size and fire the brass grows and grows until it gets to say shot #5 then it is almost fully sized to chamber dimensions.

I did much testing and measuring and found after shot 5 just neck sizing the case grew less in length .0005"
And the case was no harder to chamber at #20 neck sized vs #5.
So only then is the case really close to the same dimensions.

I anneal each time no matter which way I size the case. Now if your gun just shoots 1.25" groups you may not notice much.
What you will notice is that flier that opens a 1" group to 1.4" can sometimes be eliminated with annealing.

I did much testing there also.
Annealed vs not annealed.
I get the same bullet seating forces when I anneal.
Winchester .308 cases will have over 20 PSI different bullet seating force of annealed vs one time shot not annealed.

Annealing makes the bullet seating pressure go up.
You are probably thinking wait a minute the case neck is now softer why???

Because it has more spring back in the case neck after annealing. so as you stick a projectile into a case neck that is .002" smaller than the bullet diameter this added spring back acts like a clamp holding the bullet tighter.

You get a harder case it looses spring back and will have less bullet holding power.

This is not true for all makes of cases..Well it is .. But during testing the Lapua cases in .308 held their springiness all the way to 40 times fired and Not annealed.
85 PSI to seat a 1 time fired case and 80 PSI to seat the 40 time fired.
But even then My accuracy improved if i annealed the Lapua each time.

My FLS die is modified..I honed it so as to not size my case down but .001"-.002" anywhere.
So not your typical die.

You can have the die manufactured make a custom die for you,, send them a fired case and tell them what you want.
Lee dies are cheap and I do not mind honing one myself.

Sorry writing a book.

My guns were not as accurate just neck sizing.

 

[slas]

Lots of good info, thanks for all that. I'm using Lapua brass now in the 260 but previously when I noticed the sticky rounds after about 4 or 5 firings, only neck sizing, I was using cheaper brass, in my 308. I'll try the anneal and neck size each time and go from there. I think you are probably being much more precise than I'll even need to be. Being realistic, my main goal is to be able to clover leaf three shots at 200-300 yards and be able to put a shot in the neck of any deer I'm targeting at those ranges. I am able to do it at 200 yards with my stock Tikka CTR 308, with the right glass. I'd also like to eventually do some coyote hunting, there were several taunting me this year while sitting in the blind. Or course I may get lucky and get to do another Elk hunt some day, or......

I just ordered a Brownells Acraglas bedding kit and a Tikka upgrade kit with pillars and new recoil lug. That will be my spring/summer project before next hunting season. I figured I have all summer to get a pet load straightened out. I'd like to have one for each 120, 130 and 140 grain, my other spring/summer project......

 

[swampratt]

clover leaf 3 shots at 300 you need to pull out all the stops.
That is basically under 1/2" at 300.. with .308 I say that is a .308" group.
If you can get 2.25" at 300 for 3 you can hit anything you aim at,, If you can keep it in a 3" circle at 300 you can hit squirrels .

My 30-06 100ATR has taken a few at 300 and it holds .75 MOA all the way to 500.
Certain counties allow Gun during fall turkey.. this is when range guessing is critical and I have harvested turkey at 275 yards with rifle with no meat lost except the butt and tail end
.75 MOA Plenty to kill anything I need to kill.

 

[Rhino 55]

OK guys. I have one question. When are you ever going to shoot a clover leaf group on a deer at 300 yards? I don't think so. I build rifles as a hobby and what you need to look for is placing the bullet where you want it on a cold bore. One shot one kill. Now if you were shooting competition, shooting clover leafs at 300 yards is great.

 

[dennishoddy]

OK guys. I have one question. When are you ever going to shoot a clover leaf group on a deer at 300 yards? I don't think so. I build rifles as a hobby and what you need to look for is placing the bullet where you want it on a cold bore. One shot one kill. Now if you were shooting competition, shooting clover leafs at 300 yards is great.

That's what I tell everybody that want to listen. One cold bore shot for hunters. Give the rifle time to cool and shoot one more. Make adjustment.

 

[slas]

Maybe there was a misunderstanding of my statement. First, I said I'd like to be able to shoot clover leafs at 300(on paper), not that I had. I have shot them at 200 with the CTR 308. The reason I'd like to shoot clover leafs at 300 yards is because that would let me know that where ever I decided to aim on a deer, or any other thing I'm shooting at, I would have the confidence and experience to hit that aim point. If I can put clover leafs in paper all day at 200-300 yards with my 260 then I'll be ready for hunting season without any doubt of my abilities to humanely and accurately put down the animal.

 

[Jcann]

A clover leaf group at 300 yds kind of puts to bed the cold bore problem I would think. If you're worried about a miss on a deer at 300 yds due to cold bore variances I would bet you have other issues besides cold bore. Just my 2 cents.

Get your loads worked up and then try shooting "dot" drills.