Respect the Magazine OAL or go further?

[ceruleanblue]

My .308 Win has a max magazine OAL of 73mm. Should I respect that OAL or load longer rounds that reach closer to the lands and feed each cartridge manually? Can you elaborate? How much tighter will my group be if I go that extra longer? Maybe what I'm asking is if it makes a huge difference. I know some of you will answer that I should go shoot paper, but I'd really like to know your experience. I do paper but for benchrest 6PPC and there I have it near perfect (for me). What about for shooting 300 to 600 meters with the 308? Does it make a worthwhile difference? I can't take my rifle to a gunsmith and have them do the barrel so that it works with a shorter round. That would be a nice (but for me, an unavailable option) Thanks a bunch.

Migs

 

[918v]

Your groups may or may not be any tighter. You can get best accuracy close or far from the lands. It depends on the load and on your gun. You have to test it.

 

[ceruleanblue]

Your groups may or may not be any tighter. You can get best accuracy close or far from the lands. It depends on the load and on your gun. You have to test it.

Thank you. I'd love to know if the effort will be worth it from anyone who has this experience. (It is also a reflection of the frustration I feel others might have when manufacturers don't set their lands close to the bullet.

 

[spife7980]

Thank you. I'd love to know if the effort will be worth it from anyone who has this experience. (It is also a reflection of the frustration I feel others might have when manufacturers don't set their lands close to the bullet.

It will be worth it depending on what your barrel and component combinations like.

So yet again, you have to test to find out.

For those who do test, it is worth it because they know. Those who don’t test can’t possibly know.

 

[918v]

Thank you. I'd love to know if the effort will be worth it from anyone who has this experience. (It is also a reflection of the frustration I feel others might have when manufacturers don't set their lands close to the bullet.

Bullets vary in shape. If rifle manufacturers set their lands close to the bullet then you would have ammo problems.

 

[Supersubes]

My .308 Win has a max magazine OAL of 73mm. Should I respect that OAL or load longer rounds that reach closer to the lands and feed each cartridge manually? Can you elaborate? How much tighter will my group be if I go that extra longer? Maybe what I'm asking is if it makes a huge difference. I know some of you will answer that I should go shoot paper, but I'd really like to know your experience. I do paper but for benchrest 6PPC and there I have it near perfect (for me). What about for shooting 300 to 600 meters with the 308? Does it make a worthwhile difference? I can't take my rifle to a gunsmith and have them do the barrel so that it works with a shorter round. That would be a nice (but for me, an unavailable option) Thanks a bunch.

Migs

How long is a loaded cartridge when touching the lands with your chosen bullet?

How does the gun shoot when cartridges are loaded to magazine length?

 

[ceruleanblue]

How long is a loaded cartridge when touching the lands with your chosen bullet?

How does the gun shoot when cartridges are loaded to magazine length?

The round that is .001" off the lands is 77mm. Using a 168 gr Sierra BTMK for 1:10 twist. There is an increased spread of 5 mm on paper at 100 meters when using a cartridge that is magazine capable. At magazine length I can hit 2/3 times at a steel target (15x15cm) 400 meters out. I don't know if that is average or good.

 

[Supersubes]

The round that is .001" off the lands is 77mm. Using a 168 gr Sierra BTMK for 1:10 twist. There is an increased spread of 5 mm on paper at 100 meters when using a cartridge that is magazine capable. At magazine length I can hit 2/3 times at a steel target (15x15cm) 400 meters out. I don't know if that is average or good.

So you’ve already tested rounds loaded close to the lands, and the mag length rounds produce a 5mm larger (increased) spread?


I dont know if its average or good either, you didn't say how big the 400 yd target was, or what the baseline 100 yard group sizes.

 

[ceruleanblue]

So you’ve already tested rounds loaded close to the lands, and the mag length rounds produce a 5mm larger (increased) spread?


I dont know if its average or good either, you didn't say how big the 400 yd target was, or what the baseline 100 yard group sizes.

The 400 yd targets steel target are 15x15cm . And yes, and the mag length rounds produce a 5 mm larger (increased) spread. I'm just curious what your experience is.

 

[Mauser06]

Do you want to use your magazine?

If you do, you don't have a choice to make.


As said, every gun and bullet is different. I don't buy repeaters to load them by hand. So I start my seating depth test within the confines of my magazine.

If you wish to shoot single rounds, start in the lands and work the bullet deeper for your seating depth test.



Just like powder charges, your barrel will likely have a few nodes for seating depth.

 

[rustyinbend]

Totally depends on the "Why?" of your reloading. If you're doing it to shoot the MOST accurate results you can achieve, then by all means, feed one at a time if that is the best result. But if you're handloading to shoot in competitions or for hunting, then get the best load your magazine length will support. I want accuracy, but I'm loading for competition, so magazine fit matters to me. Loading one-at a time to get a few hundredths closer to the lands just isn't how I want or need to shoot. Everyone is different.

 

[ceruleanblue]

Totally depends on the "Why?" of your reloading. If you're doing it to shoot the MOST accurate results you can achieve, then by all means, feed one at a time if that is the best result. But if you're handloading to shoot in competitions or for hunting, then get the best load your magazine length will support. I want accuracy, but I'm loading for competition, so magazine fit matters to me. Loading one-at a time to get a few hundredths closer to the lands just isn't how I want or need to shoot. Everyone is different.

Yes, I get it. I just wonder if the trouble of going "benchrest" level reloading is what long range shooters do. I doubt it. I'm somewhat moving from benchrest toward elr/prs but we don't have that sport set up here. In elr/prs the reload has to be fast, so they use the magazine. How much are the sacrificing for it?

 

[rustyinbend]

Yes, I get it. I just wonder if the trouble of going "benchrest" level reloading is what long range shooters do. I doubt it. I'm somewhat moving from benchrest toward elr/prs but we don't have that sport set up here. In elr/prs the reload has to be fast, so they use the magazine. How much are the sacrificing for it?

Been in a few PRS matches ... loading one-at-a-time would definitely "not" work.

 

[ceruleanblue]

Do you want to use your magazine?

If you do, you don't have a choice to make.


As said, every gun and bullet is different. I don't buy repeaters to load them by hand. So I start my seating depth test within the confines of my magazine.

If you wish to shoot single rounds, start in the lands and work the bullet deeper for your seating depth test.



Just like powder charges, your barrel will likely have a few nodes for seating depth.

I'm kind of "in between" shot by shot and magazine. Maybe I should play as long as it fits the magazine with the reload. It seems like a waste not using the magazine. Maybe there are rifles that for a 308 hold longer rounds. I wonder

 

[Mauser06]

There are some different mags with different limitations. Depending on what mags yours is setup for.

I know Wyatts mags longer boxes for 700s. I believe AICS pattern mags vary by manufacturer too.

Don't hear of too many guys needing or wanting longer with a 308. Usually the bigger cartridges on Short actions are when guys start looking for longer mags or building SA clamberings on long actions to get the length they need. But they are doing that just because the mag limits them...not to reach the lands specifically.

You're right..many factory guns have the rifling a good ways in. Not sure why. Maybe just so you don't run into issues with different bullets being longer and getting jammed into the rifling.


Thats how I tackle seating depth though. If I am running a magazine and want to utilize it...I start at max mag length and don't worry about the lands. Unless max mag length has me jammed...then obviously I'd go shorter to start.

 

[KnowNothing256]

Yes, I get it. I just wonder if the trouble of going "benchrest" level reloading is what long range shooters do. I doubt it. I'm somewhat moving from benchrest toward elr/prs but we don't have that sport set up here. In elr/prs the reload has to be fast, so they use the magazine. How much are the sacrificing for it?

The targets are mostly on the order of 2 MOA in PRS, it’s not remotely a benchrest competition. Folks are typically loading for good groups, but also looking for repeatable velocities and 100% functionality. Everyone in that discipline has settled for mag-functional COLs because it’s simply mandatory.

Now, there is one workaround: run a short action cartridge in a long action. That greatly relaxes mag length restrictions, at the cost of a bit more weight (like 5-8 oz) and a slightly longer bolt cycle. If you’re running the bolt hard and fast like you should be, the extra bolt cycle length will probably be unnoticeable.

 

[KnowNothing256]

There are some different mags with different limitations. Depending on what mags yours is setup for.

I know Wyatts mags longer boxes for 700s. I believe AICS pattern mags vary by manufacturer too.

Don't hear of too many guys needing or wanting longer with a 308. Usually the bigger cartridges on Short actions are when guys start looking for longer mags or building SA clamberings on long actions to get the length they need. But they are doing that just because the mag limits them...not to reach the lands specifically.

You're right..many factory guns have the rifling a good ways in. Not sure why. Maybe just so you don't run into issues with different bullets being longer and getting jammed into the rifling.


Thats how I tackle seating depth though. If I am running a magazine and want to utilize it...I start at max mag length and don't worry about the lands. Unless max mag length has me jammed...then obviously I'd go shorter to start.

Dang it, beat me to it haha

 

[Mauser06]

Your better shooters IMO aren't sacrificing much accuracy. Might not go full blown BR with load development and loading process. But they aren't skimping.

Why not remove as much variable as you can? You're already fighting the biggest uncontrollable factor...wind. tune the gun and load as tight as you can.


Gotta remember...most guns aren't off the shelf. They are chambered with the cartridge and mag limitations in mind...if they have a good smith.

 

[918v]

175SMK @ 71.3mm. They touch the lands at 72.8mm. You can make accurate ammo at mag length, just not with every powder/primer combination.

 

[ceruleanblue]

The targets are mostly on the order of 2 MOA in PRS, it’s not remotely a benchrest competition. Folks are typically loading for good groups, but also looking for repeatable velocities and 100% functionality. Everyone in that discipline has settled for mag-functional COLs because it’s simply mandatory.

Now, there is one workaround: run a short action cartridge in a long action. That greatly relaxes mag length restrictions, at the cost of a bit more weight (like 5-8 oz) and a slightly longer bolt cycle. If you’re running the bolt hard and fast like you should be, the extra bolt cycle length will probably be unnoticeable.

I have a decent rifle but not the best. My next one will have a lot more consideration built in starting from the very most important thing: the bullet I choose to use.

 

[ceruleanblue]

View attachment 7576469

175SMK @ 71.3mm. They touch the lands at 72.8mm. You can make accurate ammo at mag length, just not with every powder/primer combination.

Yeah, I need to use a heavier bullet. I'm at 168 gr while you are at 175gr. Awesome group! (I'm not even close) ...with my 6PPC yes but not with my 308

 

[ICU22250]

Instead of worrying and drooling over touching the lands, why don't you just load to mag length and spend more time working with different powder charges or load combinations to achieve the accuracy your looking for. Single feeding sucks....

 

[ceruleanblue]

Instead of worrying and drooling over touching the lands, why don't you just load to mag length and spend more time working with different powder charges or load combinations to achieve the accuracy your looking for. Single feeding sucks....

That's a great idea. I do have some powders to try. -Thank you!