OAL to lands for Rem700P Ballpark

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GSoD

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Hey all,

Thought I would try playing with my seating depth to see if it improves accuracy.

I don't have a guage so I did two tests (I seated a bullet and pressed it into chamber with finger. If it stuck I cranked down on the seater until it dropped out by gravity and then I did the seat the bullet and close action, cranking down seater until bolt closed with ease) and both came to 2.965"

A) For any others with Rem700P in .308 who have measured their max oal (with guage or without) does this sound like the right ballpark for the distance to lands?

B) If I was seating to a OAL of 2.800 before - does that mean the bullets were making a .165 jump to the lands?

C) If I wanted to test backing off the lands for improvements in accuracy would I start at 2.955 (-10), 2.945 (-20), 2.935 (-30), 2.925 (-40).

D) Lastly, I've already found what I think my rifle likes in terms of grains of powder - 44.5grains of Varget. By adding that extra space in the case am I going to have to go back to square 1 in figuring out a good powder load? Or will these effects be minimal?

Any info well appreciated as always,

Thanks,

ST

PS - This is for 175grain Sierra HPBTs if that helps.
 
I just seat a dummy bullet way out, then chamber it and close the bolt, letting the lands seat the bullet further. Take it out and measure the OAL, then back off .010, or to fit the mag, whichever is shortest. Works for me.

Try it with your 44.5gr and see how it shoots before adjusting the charge.
 
I don't have a 700P but in my 700 SPS 308 there is no way I can get my 165gr bullets to seat anywhere near the lands and still have them fit in and feed from the mag box which measures 2.830. Just something for you to consider.
 
I think most bolt action rifles will not allow the bullet to seat to the lands and still go through the mag. Of course, it depends on the shape of the bullet, also. For accuracy, seating to touch the lands is probably the best you can get. It would be unusual, I think, for a rifle to be more accurate just because the bullets had to jump to the lands.
As far as the .165 jump to the lands, this is a nothing. Some rifles, such as the early Weatherby's had something like 3/8 or 1/2 inch jump, I think, to the lands. This is called free bore.
However, the question of accuracy for hunting rifles, whether the bullet is seated close to, touches, or some distance back from the lands, is near meaningless. We are talking in such small amounts of "potential" accuracy that it will likely never be noticed, certainly not for hunting, or general plinking. Why not just load the bullets so they will just nicely feed and forget about that aspect of accuracy?
 
Just experimenting to see how tight I can get the groups for target shooting. I know it won't feed from the magazine. My hunting loads will be mag fed.
 
H4831 said:
I think most bolt action rifles will not allow the bullet to seat to the lands and still go through the mag. Of course, it depends on the shape of the bullet, also. For accuracy, seating to touch the lands is probably the best you can get. It would be unusual, I think, for a rifle to be more accurate just because the bullets had to jump to the lands.
As far as the .165 jump to the lands, this is a nothing. Some rifles, such as the early Weatherby's had something like 3/8 or 1/2 inch jump, I think, to the lands. This is called free bore.
However, the question of accuracy for hunting rifles, whether the bullet is seated close to, touches, or some distance back from the lands, is near meaningless. We are talking in such small amounts of "potential" accuracy that it will likely never be noticed, certainly not for hunting, or general plinking. Why not just load the bullets so they will just nicely feed and forget about that aspect of accuracy?
Click to expand...



Seating to touch the lands can raise the pressures too high.....
 
303carbine said---Seating to touch the lands can raise the pressures too high.....

One of the many myths of handloading.
 
Your optimal OAL will also vary depending on what boolit your loading...
Different boolits will have different ogives....
I recently read a thing on the 700 (I own a 700pss in .308) The article mentioned that earlier runs of the rifle were manufactured with ridiculously long throats... I believe it 'cause using a stoney-point guage I can't get any boolit no matter how long to come close o the lands...
'Doesn't seem to mater though... My 700pss and my hand loads are very accurate.
 
A competent gunsmith should be able to set back the barrel and re-chamber the rifle so that you can load from the mag without having a huge jump. A modified Palma Match chamber works well for this.

On some factory rifles, just re-cutting the chamber can improve results quite a bit. Especially with VLD bullets. They like to be seated into the lands and these are the ticket if you want to get the most distance out of the 308.
 
Interesting, I had to set my 200gr SMKs back, in my .300 wm 700P, cause we were waaaay out into the lands, even at an OAL that still enabled me to mag-feed. I got the #'s at home, in my range book, if anyone's interested.
 
I have played with OAL in the 700P also, It seems to like 2.800 to 2.810, any more than that and groups seem to get larger. Using the SMK bullets also, as well as the Lapua Scenar. Seating to the lands has not improved accuracy for me at all YET...
 
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