.309 bullets in a .308 bore

[johnu]

Recently acquired some Lapua D46s from a gentleman on the forum (thanks, Bob!) These are the older ones imported by Speer - box indicates a .309 diameter and that's what they mic out at.

Any issues shooting them from a .308 Tikka? Reduce starting loads a bit? Any difference on barrel wear? Can always shoot them from my Finn 28/30!

Thanks in advance,

John

 

[MOO1072]

John,
I don't expect that you will have any problems. Like any new loads start low and work up. I use Speer 150gn Magtips in my .308 Norma and they are a .309 diameter bullet.

They should not affect barrell wear either. Barrells are generally worn out from gas erosion at the throat.

Regards
Moo.

 

[kentuckytroutbum]

My 30 cal. Sierra MK HPBT mikeout at .3085"

Bill

 

[GermanS1]

John, I've shot many, many thousands of Lapua D46 185 gr. FMJ's through many .30-06 and .308 barrels including a lot of pressure testing. No worries, work up your loads as usual.

 

[Laurie]

John,

if you only only knew what undersize barrels were produced for GB and British Commonwealth Target Rifle shooting poles in the bad old days of using the UK version of US M80 7.62mm NATO cartridges at up to 1,000yd, and what has been forced down some of these tubes since!!!

If you did, you'd NEVER worry about putting a 0.309" bullet down a 0.300/0.308" barrel. As people have said start at a modest level and work loads up. You'll likely get the best results at only marginally lower charges than you'd see with an equivalent 0.308-0.3085" design.