260AI...picture heavy

[LongRange]

LOL...your always welcome to come out and get a bolt fix.

did you take your rifle over to jack? if so you can borrow the blank i have and give me the one you ordered when it comes in.

youll be happy with the standard or the AI but if you go AI you can use this one to fire form to save a little barrel life on yours...i just ordered a head space gauge and the AI reamer .296 neck with a short .060 free bore so jack can set the free bore accordingly....im not sure on the actual drop and wind numbers on the AI vs the 260 but shooter shows 2.4 less elevation at a 1000yds but wind is almost the same...260 in a 10mph 3 o'clock wind says 50.3" and the 260AI says 49.7.

im going out this morning to get some dopes from 330 to 850 and if im not hypodermic by then i think ill reset at a 1000yds and see where im at...supposed to be a lot warmer today..LOL..but i just checked the weather and their calling for a 60% chance of snow by 8am so it looks like ill be breaking out the rain suit and the hefty bags.

[LongRange]

well it was a lot nicer today at 28deg...compared to 17degs it was like a heat wave...while the neck tension issue isnt full resolved it did shoot pretty good...i did a little test at 850yds...the 3 shots at the bottom of the target are with cases that the bullets seated fairly nice the other 3 high and to the left are 3 with the cases that the bullets kinda popped in at the beginning then kinda slid in after....



i shot 5 rounds over the chrony with 45.6g RL-17 at 28deg...
1...2965
2...2952
3...2955
4...2950
5...2952...not bad ESs for RL-17 and i think when i get the neck tension straightened out and maybe a seating adjustment this will be a real nice load...ill run it back up close to 3000fps next weekend and see how it shoots as i should have the new die by then.

[schnyd112]

Yup, Jack has my gun, he is going to gauge the action/bolt lug recess so I can order a new bolt. Shipping confirmation yesterday that my barrel has shipped so as long as it doesn't get flooded away I should have it soon.

[LongRange]

fantastic...cant wait to see how it shoots!

[LongRange]

ok guys this is almost over so bare with me for a couple of more posts LOL!!

so heres where im at...i ordered a type S FL sizing bushing die and the appropriate bushings and also ended up ordering a comp seater die because i dont like the case not being supported while the bullet seats...i should of just ordered the comp set to start with and saved myself a bunch of time and money...lesson learned...dont try to do things the cheap way if you dont have to!!
two problems with the FL die...i had to have .040 taken off the die so that it would bump the shoulder and the sizing button is to big...no matter what bushing i use the sized necks come out .290-.2905 and my loaded neck is .291-.2915 so not enough neck tension for my liking..i dont like NOT using the button but may have to...im going to shoot 20 rounds today and see how it shoots...i doubt it will be any worse than with the LCD and not that the groups were REAL bad with the LCD i just know there is a lot of room for improvement...i E-mailed redding to see if they make under sized carbide buttons like forster does.

my comp seater die shows delivered at the front door yesterday...well it wasnt MY front door LOL...ive had packs sit at my door for several days and never had one stolen and 99% of the ppl in my neighborhood are honest so im hoping someone will stop by today with it...if not ill call brownels first and then UPS monday but im pretty sure ill be ordering another seating die.

im down to 84 pieces of brass now from 107 pieces but i expected this as ive had a few pieces that ive shot over 3000fps but over all im pretty happy with the winchester brass but will most likely move to lapua when i have my other barrel re-chambered and keep the loads in the 2950fps area.

[LongRange]

well im done and heres a few closing thoughts on this AI project.

the 260AI is a fantastic cartridge and im sold on it....still wondering about barrel life but not a big concern as its not real expensive to have a barrel set back...and seeing as the barrel im using for this had 2800+ rounds through it and then sat in my safe for a few years before being set back for this project and shoots as well as it does ill be happy if i can get 1500-1800 rounds through a new barrel before setting it back...after all barrels are consumables.

as far as the speed goes...im pretty impressed...2950fps is easy money and pretty easy on brass...i can get a 142g SMK up to almost 3100fps but the win brass is only good for 2 loads at those pressures and the accuracy is only so so and not worth the ware and tear IMHO.
wind drift seems to be about the same as my standard 260 but i havent really shot in any wind to speak of so im still not 100%...elevation at 850yds is 2.25moa less VS my standard 260...AI is 17.25 with the 142g SMK and my standard 260 is 19.5 with a 140g berger hybrid so im guessing the AI might be even less shooting the berger.

a few tips if you read this and decide to built a 260AI...spend the money and buy the right dies...the lee collet will work but IMHO your not going to get all you can out of your rifle with it....i just know that i had issues with neck tension with the LCD.
stick with what works...Terry cross and Chris long are the guys that really put the 260AI on the map...H4831sc should be your go to powder with a 142g SMK,a 140g berger or the 139g lapuas with a large rifle primer. i started with a mag primer and while they worked well they were creating high pressures with only a 16fps difference in speed with the same load.
i tried H4350 which worked pretty well...RL-19 and RL-17 which worked pretty well but you will see the clear winner below is H4831sc at 48.5g as Terry Cross recommends.

ive been out twice today...once this morning to shoot loads(RL-17) i had .001-.0015 neck tension on...im not even going to post pictures the groups were so bad.
i just got back from shooting a few groups that i had .003 neck tension on...i loaded 10 with 45.6g of RL-17 and 10 with 48.5g H4831sc...

this is the RL-17...im not sure why other than a different neck tension why this load fell apart...it has shot well until now...i only shot 5 of the 10...



these are the H4831sc loads with different seating depths...im going to try .015 off the lands to make sure im not missing something but im thinking its not going to get much better than the .020 off the lands load...





after shooting these groups this morning im sure fouling was never a problem as i havent cleaned the barrel so i think 50% of the issues i was having was neck tension and 50% shooter LOL!!

[yobuck]

Could it be that those who have a reputation for building the guns, know what loads they shoot?

[LongRange]

i would have to agree but i dont like wondering if something might work better in my rifle as compared to what works in theirs...plus this was a trial run to see if i was even going to be interested and started as an expensive way to find out...well im interested and it cost me more trying to save money LOL!!

on a side note...about an hour ago the neighbor 3 doors down sent his kids over with my missing seater die in the unopened package...its nice living in a small neighborhood.

[scooterf79]

Really enjoyed following this one LR....nice to see real world tests especially comparing the AIs with the parent cart. Very informative....👍 Very nice write-up
I live in a neighborhood like that.....its very nice!
Scooter

[LongRange]

thank scooter...the next one should be interesting too.

[Dewey7271]

Nicely done LR and great thread. Glad you like the cartridge (thought you would once you wrung it out)

[LongRange]

thanks for all the info Dewey much appreciated!

i will leave you guys with this because you all know i can not leave well enough alone...long story short...since the shilen barrel that was on this rifle before i started this will soon be AI'd and i have 100pcs of fully prep'd 5-6x loaded lapua brass i thought id fire form 50pcs....i have a lot of H4350 and CCI200 primers so thats what i used.

ALL LOADS SHOT...
off bipod and cladwell rear rabbit ear bag...100yds
43.5g H4350...if it was with in .3g i dumped it in
CCI200
FL sized lapua brass
#1-#3-#5...142g SMK...025 off lands
#2-#4-#6...140g berger hybrid...seated .030 off lands
#3 and #4 shot over magneto speed chrony...10 shot groups
#1 and #2 first 5 shot groups
#5 and #6 10 shot groups
50 rounds total...

[Dewey7271]

Anytime!
Sweet fireforming!

[GaCop]

I guess when I get some wear in my 260 Rem barrel I'll have to consider having it AI'd!