I was introduced to a tool 2 nights ago called the stoney point overall length gauge.I have heard of this tool before but never had one near my rifles.My Tikka T3 hunter 300 winmag has shot under .75-.50 MOA groups with 165gr &180gr nosler bullets.I thought based on a smoked bullet and accuracy results that I was close to the barrel lans.I have always loaded to 3.362", the max my clip would allow.I measure the chamber the other night and I am allowed 3.591"chamber AOL.I am thinking of loading some cartridges and shoot individually and do some close to the lans load developing.I can always carry the long loads in for the loong shot and load regulars for the 300yd+/- shooting.Am I being foolish?The rifle shoots 4 in .5 MOA with 180gr Accubonds or baltips.Will I get to that elusive .25MOA with the longer loads or am I being crazy.
I did buy the magnum for long range hunting. hunting.responses appreciated RB

ruttinbuck,

If you haven’t bought the AOL gauge yet you should consider the Sinclair Seating Depth Tool
as it is more accurate, and less expensive than the Stoney Point if you are reloading for several calibres (no need for modified cases!).

B.Martins

Hello ruttinbuck,

Seated at that maximum length you mentioned I'm surprised there's enough space left to hold the bullet securely. I also use the Stoney Point OAL guage and like it a lot. I found there was a bit of a learning curve involved but have no problem with it now. I'm amazed at the lengths of the chambers manufacturers are turning out today. It's like they've never heard of SAAMI recommendations. Best wishes.

Cal - Montreal

RB, like you, like most of us, I want my guns to be as accurate as possible. If I miss or make a poor shot, I want to know it was me and not the gun that screwed up.

But, 0.5 MOA is just 2 inches at 400 yards. With all the other variables in a hunting situation - wind, temperature, altitude, angle up or down, correct distance?, etc. - I think anything under 1.0 MOA is just gilding the lily. Without a benchrest or sandbags, it's awfully hard to duplicate that 0.5 MOA you shot last summer.

Of course, you could always buy something with a more generous magazine and sell me that 0.5 MOA Tikka.

I know what you are saying Hornhunter.I think I will just live with the groups it shoots now.The rifle can shoot better than I can when excited and huffing-puffing.I just want all angles covered and wring the last ounce of accuracy potential out of the rifle.I may try some loaded to chamber length rounds and see how tight the groups will get.RB

RB, if I may make a suggestion or two.

Per your numbers, you're way off the lands right now. If you're going to start with the bullet seated at or very close to the lands, back off on the powder charge 2-3 grains.

As an alternative, you could increase the OAL in several increments, watching for signs of excessive pressure as you go.

Go for it.