freebore in AIAW

[jbell]

I am working up some handloads for a friends AIAW (2007 vintage) it is chambered in .308 win factory barrel. I am using Sierra match kings in 168g and 175g. I measured the chamber today with my Sinclair tool for both bullets. This tool works very good but is designed for a action w/ a smaller diameter bolt so the fit in the AI was a little loose, so I am not confident in my measurements. If I had the rifle here I could use a loaded round to determine the "jam" by watching the land marks and seating deeper untill they disapear. From my measurments it looks like the rifle has a lot of freebore as compaired to my TRG (like .050-.100 in more). Does any one have any experiance with this combination? Does anyone have any jam measurements for there AIAW , please include your method of measureing ie. tip to base or ojive to base and include the compairator measurement if it is included in your jam numbers. Thanks for any info provided.

 

[bm11]

Re: freebore in AIAW

Bump for my rifle!

 

[desertHK]

Re: freebore in AIAW

I have gone through two AIAWs in 308. The first one was an 07 model and the second one was an 09 model. There is a difference in the chamber length. Using the Hornady OAL gauge method, the 07 model has an OAL length of about 2.920" for the 175 SMK (Yes, jamming it into the lands). So I loaded at 2.910" OAL. WIth the 09 model, using the same method, the OAL is about 2.900". I load it at 2.875". Hope that helps. It seems that the newer model has a shorter chamber length than the older model. However, that's just one man's experience. FWIW.

 

[jbell]

Re: freebore in AIAW

Thank you deserthk, I just compaired your measurements with those I took from bm11's rifle and the measurements of my TRG. It seems to me your 2 rifles are very close to my TRG. I must have took inaccuriate measurements in bm11 rifle due to the guide being very sloppy in the larger bore in the AI action. The guide was very loose and despite my best efforts to keep everyting the same whial measuring I was off quite a lot (like .100in longer). I will try seating the bullets long and then backing them up untill the land marks disapear the next chance I get to meet w/ bm11. Thanks for your info, I would like to hear from anyone else who has experiance w/ loading for these fine rifles.

 

[bm11]

Re: freebore in AIAW

Jbell,

I think perhaps if you repost this thread in the reloading forum, you might get a bit more action?

-BM

 

[jbell]

Re: freebore in AIAW

Good call Ill try it. I actuall have been thinking about that.

 

[awp762]

Re: freebore in AIAW

Posted data in reloading section for you

 

[lvmike]

Re: freebore in AIAW

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DesertHK</div><div class="ubbcode-body">I have gone through two AIAWs in 308. The first one was an 07 model and the second one was an 09 model. There is a difference in the chamber length. Using the Hornady OAL gauge method, the 07 model has an OAL length of about 2.920" for the 175 SMK (Yes, jamming it into the lands). So I loaded at 2.910" OAL. WIth the 09 model, using the same method, the OAL is about 2.900". I load it at 2.875". Hope that helps. It seems that the newer model has a shorter chamber length than the older model. However, that's just one man's experience. FWIW. </div></div>

My 09 is the same, however I have had the best luck with my factory 20" barrel with much more jump then that. I'm currently at 2.820" coal with a 175smk, lapua brass, cci br2, and 45gr of varget.