243AI and RL17

[JJH]

I have been working up some loads with RL 17 and have been curious about it's performance in my rifle.

With two different bullets, I have had trouble with pressure signs at loads that are not what I would consider hot looking at velocity.

85g Speer BTSP
Alliant shows a max charge of 43.7 at 3316 in the parent cartridge.

Working up my load in my AI, 44g I began to show pressure signs that scared me off of going higher, including sticky bolt, and ejector marks on the case head.

I stuck with a charge of 43.5 at 3281. I don't have the chrono data on the 44g load, as its lost on my laptop that crashed a while back.

I most recently have been working on a 70g TNT over RL17. There is no data from Alliant on the parent case, but I used the 6mmRem data. Reduced 10%

I am still only able to hit about 3500fps without the pressure signs showing up. Alliant data shows 3600fps from the 6mmRem.

Is the 17 just too slow in my gun? Obviously each bore is a touch different, considering the short life of these barrels, I really hate to waste a whole lot of time on another entire workup with an ill suited powder.

 

[.260 james]

I have used Reloder 17 in a .260 and a .243 and so far my results have been completely the opposite of yours. I have worked up a load for each gun that once a safe reasonable maxium working load was found, velocity tended to be alot higher then i anticipated. I have yet to chrony the loads for the .243 yet with 95 gr. berger hunting vld but i suspect they will follow the same trend.
This a both hunting guns and i work up slowly watching for accuracy and pressure signs then chrony once a good load is found.

 

[kjcpoint]

Give H414 a try for the 70gr bullets. Works great in mine and a buddies.

Kyle

 

[stebbins243]

I have used Reloder 17 in a .260 and a .243 and so far my results have been completely the opposite of yours. I have worked up a load for each gun that once a safe reasonable maxium working load was found, velocity tended to be alot higher then i anticipated. I have yet to chrony the loads for the .243 yet with 95 gr. berger hunting vld but i suspect they will follow the same trend.
This a both hunting guns and i work up slowly watching for accuracy and pressure signs then chrony once a good load is found.

Right there with you. My .243 is a crazy man on that stuff. Ive loaded past max and still have very little pressure signs and judging from bullet drop ive picked up serious velocity. Im curious why the AI is doing that.

 

[dtucker]

I second this. I have had very good results with H414 also.

Give H414 a try for the 70gr bullets. Works great in mine and a buddies.

Kyle

 

[calib]

use the win 760 when shooting my 70grn nosler bal tips out of my slow twist ai
i think i am running like 3650fps or so

and reloader 22 with 95 grain bergers in my fast twist shooting real accurate at about 3150fps

 

[JJH]

It's interesting that I am getting the pressure signs that I am getting, after hearing so many good results for others. After I back from p-dogging I am going to work up another time with a different manufacturer's bullet. I may need to slug my bore, I'm wondering if I may have a slightly under size bore, or if maybe the Speer bullets are running oversize.

I can't decide if I just need to use different powder (faster/slower), or if its a bore size issue, or what the heck is going on.

Feels like a waste having that extra case capacity, and not being able to utilize it. And the limited barrel life of the AI, i hate burning it up with what isn't working.

 

[kjcpoint]

I shoot 68gr match bergers with 49.5gr of h414 @3865. Krieger 11.5 twist?

What kind of action are you using and what twist barrel?

Kyle

 

[JJH]

I shoot 68gr match bergers with 49.5gr of h414 @3865. Krieger 11.5 twist?

What kind of action are you using and what twist barrel?

Kyle

Rem 700, Douglas 1-10.

 

[.260 james]

How does your gun react to other powders, does it seem to build pressure early with others also??????? I have started low with my guns and rL 17 and used bullets not listed for data and always ended up past where I thought I would. Your gun may just build alot of pressure and require a slower powder ie H4831 or something like it.
In the past I noticed Speer bullets seemed to build more pressure then sierras or hornadys of equal wieghts in my guns.

 

[AckleymanII]

kjcpoint, I have owned multiple guns that shoot your load

My rifle loves 48.5g of Win 760, Rem case, CCI 250 primer and is 3850 fps shooting tiny groups.

I think that this gentleman has a tight bore, or it is full of copper.

 

[JJH]

How does your gun react to other powders, does it seem to build pressure early with others also??????? I have started low with my guns and rL 17 and used bullets not listed for data and always ended up past where I thought I would. Your gun may just build alot of pressure and require a slower powder ie H4831 or something like it.
In the past I noticed Speer bullets seemed to build more pressure then sierras or hornadys of equal wieghts in my guns.

It's only the second powder I have really played with. Previously I was using 4831sc and loads seemed to be much more predictable, but I did not work too many loads. A very small sample size of one load.

It's not copper fouled, I know that. Tight bore is my guess. I should slug the barrel to find out.