Seating bullets further out?

engineer40

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May 5, 2015
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977
Location
Rockford, MI
So far I’ve only reloaded within COAL specs found in reloading manuals.

I was listening to a coworker talk about how surprised he was at his accuracy increasing when he started seating his bullets further out. While this isn’t new news to me, instead of just taking his suggestions I thought it would be wise to double check with you fine folks. :)

I understand it’s dangerous to load the overall cartridge length too short. However, with a bolt action, is it safe to load the overall cartridge length as long as I want assuming it still cycles in the action fine without actually touching the lands?

Also, is there a general distance off the lands that is “usually” known for producing the best accuracy? Example; between 0.00X and 0.00X off the lands is where someone should start testing for accuracy? (I realize every rifle is different. But with so many different ammo and rifle manufacturers, I’m guessing ammo from the factory is usually overly cautious on tolerances).

FYI… I’m more prone to start at a safer distance and work my way up while keeping track of accuracy.

Thanks everyone!
 

g0rd0

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Mar 9, 2012
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New germany, NS
with each new type of bullet I use I make a dummy (un primed no powder sized brass), I lube the inside of the neck and place a bullet into it just to hold it, now I chamber it. The bullet seats as it contacts the rifling, from there I put it into the shell holder raise the ram and with the seat plunger screwed all the way up screw the seat die down on the dummy, measure the oal and subtract 30 thou that is my start point.
Some of my rounds I load on the lands, some say this is not a good thing to do but I have found no ill effects. My 7rm likes 150's on the lands and 175's 25 thou off the lands
 

engineer40

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Joined
May 5, 2015
Messages
977
Location
Rockford, MI
with each new type of bullet I use I make a dummy (un primed no powder sized brass), I lube the inside of the neck and place a bullet into it just to hold it, now I chamber it. The bullet seats as it contacts the rifling, from there I put it into the shell holder raise the ram and with the seat plunger screwed all the way up screw the seat die down on the dummy, measure the oal and subtract 30 thou that is my start point.
Some of my rounds I load on the lands, some say this is not a good thing to do but I have found no ill effects. My 7rm likes 150's on the lands and 175's 25 thou off the lands


That is exactly the information I was interested in. I don't know if I've ever got a better answer to one of my questions...
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.
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Obviously... I must be getting better at asking questions. :)
 

7magcreedmoor

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May 23, 2012
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718
Location
Lebanon County PA
Berger has an excellent posting on their website on this subject. The test involves shooting test loads starting (for hunting rifles) 15 thou off the lands, then progressively shorter in 40 thou increments. I have used this method in my last few rifles with very efficient results. Doesn't take a lot of wasted ammo to dial in the ideal COAL.
 

barefooter56

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Joined
Nov 10, 2014
Messages
913
So far I’ve only reloaded within COAL specs found in reloading manuals.

I was listening to a coworker talk about how surprised he was at his accuracy increasing when he started seating his bullets further out. While this isn’t new news to me, instead of just taking his suggestions I thought it would be wise to double check with you fine folks. :)

I understand it’s dangerous to load the overall cartridge length too short. However, with a bolt action, is it safe to load the overall cartridge length as long as I want assuming it still cycles in the action fine without actually touching the lands?

Also, is there a general distance off the lands that is “usually” known for producing the best accuracy? Example; between 0.00X and 0.00X off the lands is where someone should start testing for accuracy? (I realize every rifle is different. But with so many different ammo and rifle manufacturers, I’m guessing ammo from the factory is usually overly cautious on tolerances).

FYI… I’m more prone to start at a safer distance and work my way up while keeping track of accuracy.

Thanks everyone!
engineer40,
7magcreedmore steered you in the right direction. Eric's article "VLDs,making them shoot" can be found under the INFORMATION tab on our main page under TECH TALK. Also down on the right side of the main page in the tan bubble. Check out Brian Litz's 2 part article under EXTERNAL BALLISTICS " Effects of Cartridge overall length (COAL) AND case to ogive (CBTO ). The down side is that you MAY end up with a single shot rifle. For Target shooting this is no big deal but for hunting it may be. Bullet seating depth tools ETC can be found on SINCLAIR INTERNATIONAL website. If you need any help please contact us either here or at [email protected].
 

DUSTY NOGGIN

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Joined
Mar 18, 2015
Messages
749
Location
salt lake city
I was listening to a coworker talk about how surprised he was at his accuracy increasing when he started seating his bullets further out.

Example; between 0.00X and 0.00X off the lands is where someone should start testing for accuracy? (I realize every rifle is different. But with so many different ammo and rifle manufacturers

Thanks everyone!

using the right tools and being certain your measurements are right is more important as you get closer

loading touching the lands is IMO for someone with full understanding of the their rifle chamber , the tolerances of their measuring tools

shoulder setback is another measurement you should to be aware of when seating close -
 

DUSTY NOGGIN

Well-Known Member
Joined
Mar 18, 2015
Messages
749
Location
salt lake city
I was listening to a coworker talk about how surprised he was at his accuracy increasing when he started seating his bullets further out.

Example; between 0.00X and 0.00X off the lands is where someone should start testing for accuracy? (I realize every rifle is different. But with so many different ammo and rifle manufacturers

Thanks everyone!

using the right tools and being certain your measurements are right is more important as you get closer

loading touching the lands is IMO for someone with full understanding of the their rifle chamber , the tolerances of their measuring tools

shoulder setback is another measurement you should to be aware of when seating close -

closer isn't always better - but you never know til you try
 

just country

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Joined
Aug 6, 2014
Messages
1,651
Location
78154
morning, different bullets have different overall lengths and ogives, if I change bullets as to what I have been shooting. use the dummy bullet theory.

every chamber has a different length. Remington's r notorious for having short throats. if u have custom barrel put of a pet action, u can ask the smith to make u a dummy round to get an idea of the length of the throat in the chamber.

Weatherby's r a different story. they r made with free bore.

good example, this person bought a Howa 257 weatherby . the person loaded some 100gr. TSX. the person loaded the rounds to set the bullets to touch the lands. all he accuracy he could get was + to - 1.50-2.00". had the smith put on a shilen barrel and the results were the same. the person tried different powders, bullets primers, to no avail.

being this a weatherby round and the free bore goes with the chambering. the smith ask the person how the person was loaded the rounds. the person explained his process. the smith told him to put x amount of free bore in the rounds. needless to say the rifle shoots .50 groups. this is a true story. I have a 257Bee this was not me!!

just countrygun)
 

Mike 338

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Joined
Feb 4, 2012
Messages
1,799
Location
Boise, ID
Berger has an excellent posting on their website on this subject. The test involves shooting test loads starting (for hunting rifles) 15 thou off the lands, then progressively shorter in 40 thou increments. I have used this method in my last few rifles with very efficient results. Doesn't take a lot of wasted ammo to dial in the ideal COAL.

+1. I more or less begin load development doing this.

I use the Hornady COL guage to determine where the bullet touches the lands. You need to buy (cheap) or make a special case to use with this tool but after using it a few times, I see the advantages of the system.
 

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