.243 AI starter loads

[Bdanley]

I have a .243 AI nearing completion. I plan on shooting heavy long range bullets 105gr Amax, 107gr SMK, 115gr Berger VLD...ect. I was wondering about starter loads. I have tons of data for a standard .243. AI data seems kinda scarce though. The guys at Berger advised that 1.5 grs below a .243 max loading is a good place to start for their bullets. Is that a good place to start for all loads? Any help would be great.
Thanks
Bryan Danley

 

[cmillard]

i would go with what berger said and load up a bunch of winchester or lapua brass and seat the bullets out to a jam and fireform. once all the forming is done, find the sweet spot that your barrel likes

 

[mj2evans]

I went with the cream of wheat method due to a .270 neck being too tight on factory 243 ammo. Using turned Lapua cases, 105g AMax, H 4831SC, and Wolf LR I get sub 1/2 MOA (at 100yds, have not tested farther). 44.5g H4831SC in a Shilen 1-8" has been a consistently good load at 2,955 fps. This speed is only about tops for a standard 243 but I didn't get better accuracy going faster. Tried Sierra 107 and it shot well but not better (and AMax are only $20 per 100). H4350 gave more speed but less accurate. I started the AMax .02" off the lands and that was the best after I started moving closer (same for Sierra). I never actaully jambed the bullets but again I though sub 1/2 MOA was good enough for a fun gun (I am not a benchrest shooter - just a paper puncher and hunter).

 

[chino1969]

I have a .243 AI nearing completion. I plan on shooting heavy long range bullets 105gr Amax, 107gr SMK, 115gr Berger VLD...ect. I was wondering about starter loads. I have tons of data for a standard .243. AI data seems kinda scarce though. The guys at Berger advised that 1.5 grs below a .243 max loading is a good place to start for their bullets. Is that a good place to start for all loads? Any help would be great.
Thanks
Bryan Danley

Bryan,
Unless you are an experienced handloader and familiar with Ackley quirks, it is prudent to follow the fellows at Berger.

Lou Baccino

 

[Bdanley]

Cool thanks!!

 

[Bdanley]

...I meant to finish that
I have plenty of handloading experience but only in standard calibers not any in Improved or wildcat loads. MY rifle will be built based on a Savage Accutrigger target action and mated to a Douglas XX 30" barrel 1:7 twist but I don't know how many grooves; all resting on a H.S. stock. I'm hoping to have it before Thanksgiving but we'll see. I've enjoyed pushing my .223 Rem as far as it will go, but I wanted to go farther....on a budget

 

[Benjerman08]

Chino,
What are some of the quirks?

 

[chino1969]

Chino,
What are some of the quirks?

Quirks may have been the wrong word but here's what I meant based on having several A.I. calibers over the years.

You can get into an overpressure situation with an Ackley with none of the normal signs. Because the Ackley chamber removes a good deal of taper from the parent case, the resultant rearward forces are reduced. Typical overpressure signs like flattened primers may not show up and you may be in an overpressure situation. Then again, you may see flattened primers in your first inspection of newly fireformed rounds and be completely safe due to the case slamming back into the bolt face, the shoulder blowing out to the 40 degree angle and reconnecting with the bolt face. One really needs to pay attention in learning to read an Ackley to learn some of the differences from the parent cartridge. Use of a chronograph will help to assess what is going on, provided you know what to look for. I'm on my 8th Ackley chambering and have learned quite a bit. For example, when fireforming brand new brass I go right to the previous fireforming load. This turned out to be a rather non conservative load (i.e. 'hot') in the parent cartridge. I found, through experience, a rather stiff load is required to blow the shoulder out properly so the lines are sharp and not rounded. With a properly chambered Ackley, there should be a .004 crush fit when you chamber virgin parent brass and the bullet should be a slight jam in the throat. The bolt should require some cam down pressure to close. When the round is fired, the bullet has already centered the brass and the crush fit serves to hold the case in the proper relationship with the chamber. The bolt will also open easily as opposed to before fireforming. The end result is a perfectly fireformed case with a nice sharp shoulder. I always go up, in charge weight, from my initial fireforming load until I find my sweet spot or optimal charge.

If you are a newcomer to the Ackley field of worship, my recommendations would be to already possess a mastery of reloading skills. Read everything you can about Ackley chambers and ask many questions. Be prepared to go through barrels more quickly but that's the price you pay.

Lou Baccino

 

[Bdanley]

I under stand the rigors of fireforming, I was thinking once the cases were formed they would act like standard caliber cases, i.e. stiff bolts and flattened or pierced primers were a good indicator of overpressure. If that may not always be the case what is some of the things I need to be looking for. While I'm on the subject what is barrel life like? As I said I plan on shooting the heavier target bullets so there should not be a need for superfast velocities.

 

[Benjerman08]

Lou,
Excellent reply. I thought you might bring up the "easy to overheat" quirk. I found this out the hard way a few years back when I first starting shooting my .243 Ackley. Ruined some good Lapua brass by trying to get the 115 dtacs to go too fast. The cci primers showed only a slight flattenening. The next time I loaded, about half of my primer pockets were already too loose and most of the empties would not go into the shell holder as the case heads (web) were expanded. I now use strictly federal primers as they are softer and show the heat coming on faster. Wonderful gun after learning the hard way though. Shoots great from 100 to 1000. Lou, did you see any accuracy difference with the non fireformed loads compared to fireformed? Bryan, read Lou's reply and take it to heart. The heat can sneak up on you in an Ackley with out you knowing it. I suggest federal primers until you get everything figured out. Mic your cases at the bottom when you are working up toward hotter loads as this is a common overpressure sign in Ackleys. I am using big 115 dtacs and have good luck with Reloader 25 (49 gr.) and H1000. Getting 3050 fps and I am satisfied with that as it is accurate and may save my barrel a little. I am off of the lands. Hope our posts save you some trouble. TF