Distance to lands

[Abolt]

I just got my first custom barrel put on a rifle. I was starting to load up a few to test it out and was checking the distance to the lands. I am using a Hornady oak gauge and a bullet comparator. With the 165g tsx the lands are 2.2660. I was going to start 50 thousands off. Loaded up the first one and its deep in the case.

So I took the bullet comparator off to find the oal and distance to lands of several different bullets. It looks like my distance to lands is the same as book oal for most bullets.

Just wondering if this is good, bad, normal, or strange? The rifle is a browning abolt 300 wsm with a bartlein barrel.

Bullet. / Book oal. / Distance to lands
Barnes 165 tsx. / 2.860 / 2.850
Berger 185 vld htg /2.860. / 2.9145
Berger 165 class htg/ 2.860. / 2.8610
Hndy 165 btsp. / 2.8235. / 2.8340

 

[200plus]

Why are you going 50 off how did you come up with that number? Did you zero calibers out before taking measurement? The numbers have listed doesn't look right.

 

[Abolt]

50 was just a starting number I thought I had seen Barnes recommend.

The first picture with the calipers reading 2.8500 is where the Barnes 165g tsx bullet stops against the lands.

The second is measuring the width of the bullet to ensure they are calibrated correctly

Third picture is a factory loaded federal premium 165g Barnes Tripple Shock I had laying around for comparison.

Thanks for the help

 

[Abolt]

Second

 

[Abolt]

Third

 

[Abolt]

I also checked the headspace on my one bullet I loaded, the factory loaded round and my modified case I have for the oal gauge and all were within 3 thousandths

 

[243winxb]

Gauging Success - Minimum Headspace and Maximum COL | World's Largest Supplier of Firearm Accessories, Gun Parts and Gunsmithing Tools - BROWNELLS

You want the shank of the bullet, full diameter, in full contact with the case neck. If the OAL will not fit magazine, or is contacting the rifling, reduce the OAL shorter.

Measure from case head to bullet ogive after seating into the rifling. The back off .010" then .020" and so on. The bullet ogive should not go below the case mouth. Test.
http://www.brownells.com/.aspx/lid=...g_Success___Minimum_Headspace_and_Maximum_COL

 

[243winxb]

I also checked the headspace on my one bullet I loaded, the factory loaded round and my modified case I have for the oal gauge and all were within 3 thousandths

Case head to bullet ogive? .003" Bullet should not be in the rifling then.

The length of the bullets, if close, should be ok.

Bullet construction , all copper to lead core, jacketed can produce very different pressures. Try to find data with the bullets your using.

I am sure you already know this, just can't be to careful.

 

[243winxb]

Getting the Best Precision and Accuracy from VLD Bullets in Your Rifle | Berger Bullets Blog

This was the Berger info for VLD bullets.. It was posted to let reloaders know that bullets dont need to be jammed into the rifling to shoot well.
http://www.bergerbullets.com/getting-the-best-precision-and-accuracy-from-vld-bullets-in-your-rifle/

 

[Abolt]

Sorry for the confusion I think I jumped into several different measurements. What I'm wondering about is if I simply loaded to book published OAL then with this rifle I would be right around the lands.

Bullet_____________Book oal_______ OAL That touches lands.

Barnes 165 tsx______2.860__________2.850
Berger 185 vld htg___2.860__________2.9145
Berger 165 class htg_2.860__________ 2.8610
Hndy 165 btsp______2.8235_________2.8340


Looking at the above if I loaded the Barnes bullet to the published OAL they would be .010 JAMMED INTO the lands

Berger 185 would be .0545 off the lands

Berger 165 would be .0010 from the lands

Hornady 165 would be .0105 from the lands.



Saying all of this to say are custom barrels normally chambered like this

Sorry if this just muddies it up more, thank you for taking time to help

 

[243winxb]

You give the gun smith the head to ogive* measurement you want the barrel chambered too. Or he will install the standard SAAMI chamber.

 

[243winxb]

Ogive Effects of COAL and CBTO | Part 2 | Berger Bullets Blog

 

[Abolt]

You give the gun smith the head to ogive* measurement you want the barrel chambered too. Or he will install the standard SAAMI chamber.

Thanks for the help. That makes sense that they would chamber to saami specs. I guess I'm just used to factory rifles with long throats. Thank you for getting me squared away and all the links. I hope to try it out Friday and see how it does. Thanks again

 

[243winxb]

lands are 2.2660.

2.316" SAAMI Looks like your head to ogive is shorter by .050" Leaves room for throat erosion over time. Should go well on fri. Good shooting.