Magazine v. Accuracy

[tommygun13]

CBTO reloaded by me was always gauged on getting the tip of the bullet as close to the lands as possible without touching to reduce wobble. The measurement was found by taking 10 rounds of recently fired brass, loading to different CBTO lengths and loading, until a length that was the longest stayed the same length after ejection. Any that were too long would stick a bit and, contrary to thinking it would be shoved down shorter, it would come out longer due to the slight stick from being wedged against the lands.The downside has always been the cartridge will be too long for the magazine. This has been a big pain when shooting. I have run tests and found the longer cartridge to be a bit more accurate, but perhaps I was a bit biased and subconsciously skewed the results. Anybody have any comments or suggestions.

 

[bfoosh006]

Load to the length your magazine will accept.
Chasing the lands on a AR firearm , will only frustrate you.

And while you may have seen some of your reloads shoot tighter groups... not being able to load a full mag and getting it to function 100% , is self defeating.

FWIW, I have seen numerous factory loads that defy conventional reloading wisdom. ( Loaded to the lands )
One from many years ago, the Federal .223 50gr Tipped Varmint load ( no longer produced ) , the bullet was "miles" away for the lands, mass produced, in common .223 brass, with line loaded powder charges.
It would produce just over 1MOA , 10rd groups, in just about any random AR15 I saw it shot from.

I truly miss that specific ammo... it was a bargain, ( $5.29 per box was the cheapest I saw ) and IMHO, was perfect for 100yd "precision" training.

Pic to show the loaded rounds bullet.... and typical accuracy... including a 20rd group.

 

[FUNCTIONAL]

I've been finding there is usually a good seating depth node really far from the lands... like .100"+. I would start at max mag length then test shorter and shorter until it's unsafe.

 

[lariat]

Load to the length your magazine will accept.
Chasing the lands on a AR firearm , will only frustrate you.

And while you may have seen some of your reloads shoot tighter groups... not being able to load a full mag and getting it to function 100% , is self defeating.

FWIW, I have seen numerous factory loads that defy conventional reloading wisdom. ( Loaded to the lands )
One from many years ago, the Federal .223 50gr Tipped Varmint load ( no longer produced ) , the bullet was "miles" away for the lands, mass produced, in common .223 brass, with line loaded powder charges.
It would produce just over 1MOA , 10rd groups, in just about any random AR15 I saw it shot from.

I truly miss that specific ammo... it was a bargain, ( $5.29 per box was the cheapest I saw ) and IMHO, was perfect for 100yd "precision" training.

Pic to show the loaded rounds bullet.... and typical accuracy... including a 20rd group.
View attachment 8507500View attachment 8507501

This. There is a difference in reloading for a bolt gun and loading for an AR. If it doesn’t feed reliably out of a mag it isn’t a good load no matter how accurate it is - it defeats the purpose of being a semi-auto.

 

[rustyinbend]

Same advice for AR10's ... like my LWRCI REPR MK2 in 6.5-CM. Load to the magazine max length and fire away. A land-seated bullet will, in my experience, pretty much always be too long for the magazine ... and single-loading AR's is just goofy. That said, it's always good to do a final check on seating and make sure you're not crunching the bullet against the lands, even on an AR loaded to max mag-length.

 

[tommygun13]

Gunny, you are absolutely correct as to single loading gassers is goofy, but I have a bolt. Bottom line for me is, for precision bench shooting only, single loading so the tip of the bullet is not quite kissing the lands is the trade off for a bit more accuracy. I only use the empty mag to keep the cartridge from falling out when I clumsily try to stick it in the rifle.
When I was in 2-2-2 1956-1959 we had M-1s. It was "This is my rifle, this is my gun, this is for shooting, this is for fun.

 

[Im2bent]

Gunny, you are absolutely correct as to single loading gassers is goofy, but I have a bolt. Bottom line for me is, for precision bench shooting only, single loading so the tip of the bullet is not quite kissing the lands is the trade off for a bit more accuracy. I only use the empty mag to keep the cartridge from falling out when I clumsily try to stick it in the rifle.
When I was in 2-2-2 1956-1959 we had M-1s. It was "This is my rifle, this is my gun, this is for shooting, this is for fun.

What mags are you using and why is this in the semi auto forum if it's a bolt gun

 

[msgriff]

What specific firearm/barrel/chambering are you loading for?

 

[Hickswr]

Answer to your question is bullet dependent. Some like to jump and others like to kiss.

 

[hlee]

Regardless of semi auto vs bolt action, loading beyond the length restriction of the magazine system is dumb.

 

[hlee]

Answer to your question is bullet dependent. Some like to jump and others like to kiss.

And, confusing the 2 could get you a restraining order…

 

[johnnyvw]

Load to the length your magazine will accept.
Chasing the lands on a AR firearm , will only frustrate you.

And while you may have seen some of your reloads shoot tighter groups... not being able to load a full mag and getting it to function 100% , is self defeating.

FWIW, I have seen numerous factory loads that defy conventional reloading wisdom. ( Loaded to the lands )
One from many years ago, the Federal .223 50gr Tipped Varmint load ( no longer produced ) , the bullet was "miles" away for the lands, mass produced, in common .223 brass, with line loaded powder charges.
It would produce just over 1MOA , 10rd groups, in just about any random AR15 I saw it shot from.

I truly miss that specific ammo... it was a bargain, ( $5.29 per box was the cheapest I saw ) and IMHO, was perfect for 100yd "precision" training.

Pic to show the loaded rounds bullet.... and typical accuracy... including a 20rd group.

I agree. I have 4 ARs and two 556/223 bolt guns. They all have very long leads to the lands compared to SAAMI specs. I wouldn't be able to load close to the lands on any of them. And checking base to ogive on about a dozen factory loads (mostly 223) they all end up 1/8" from the lands more or less. Some match grade rounds shoot sub-moa, regular "plinking" ammo shoot typically 2-3 moa...some are better but round to round consistancy seems to be the biggest difference, no matter what the weight of the bullet is. I actually found Norma TAC 55gr rounds shoot darn close to match rounds in some of my guns

 

[rustyinbend]

Right ... bolt action ... missed that.

I use these instead of magazines when I single-feed. Got one that fits my MPA chassis, and one that fits my Tikka.

Single Feed Magazine Sled - (AICS Pattern)

If you have a rifle compatible with ACIS pattern mags and you need single-shot capability, Anarchy Outdoors has the answer for you. Get your ACIS single shot sled today!

www.anarchyoutdoors.com

 

[bfoosh006]

Ok... now that it is a Bolt Action we are talking about. That changes my answer quite a bit ! Lol

 

[johnnyvw]

Right ... bolt action ... missed that.

I use these instead of magazines when I single-feed. Got one that fits my MPA chassis, and one that fits my Tikka.

Single Feed Magazine Sled - (AICS Pattern)

If you have a rifle compatible with ACIS pattern mags and you need single-shot capability, Anarchy Outdoors has the answer for you. Get your ACIS single shot sled today!

www.anarchyoutdoors.com

Geez...those things cost almost as much as a magazine

 

[rustyinbend]

Geez...those things cost almost as much as a magazine

Yes, but you only need one of them.