Setting Overall Length-I'm Getting Spooked

[brycealbright]

A friend of mine and I have been using the Hornady Lock-N-Load curved O.A.L. gauge and a micrometer to measure O.A.L. on a Colt and an Alexander Arms AR-15, 223 caliber.
To be honest, I'm about ready to throw out the entire project and just reload by the book. That's because I'm unsure about seating the bullets the correct depth, not knowing who is credible on YouTube.com and their demonstrations. Any recommendations on this?

[SonOfGun]

OAL is not carved in stone. It is a guideline. Use a length that best fits your firearm, chamber and magazine.

[4runnerman]

I am not sure I understand your question here. Use the guage, shove bullet out till it hits the lands, do this at least 5 or more times.( just to double check your measurments) Measure the length. That is your Max length. You must also make sure your Mag will handle that length too.
It is a very easy thing to do. Some will tell you to reduce powder load 10% and work back up when you are right off the lands. Safe is better,but I have never found the reason to do so.

[Bart B.]

Seat bullets just deep enough to feed reliably from the magazine. That's been the standard for decades. If they're too long for the chamber, whoever chambered the barrel should fix it with no cost to you unless they cautioned you about it.

Only if you'll load rounds one at a time for slow fire, single round loading for rifle competition should you be concerned about seating bullets to ant longer lengths.

Most publishers of load data for semiauto ammo are not smart enough to list overall length as what feeds reliably from magazines. They should also mention there's a few hundredths inch spread in ammo length that ammo will shoot equally accurate in. That's how far the origin of the rifling erodes away every thousand rounds. Are you going to seat bullets a couple thousandths inch less every hundred rounds to keep bullet jump to the rifling distance pretty constant until you consider it worn out? People winning matches and setting records don't.

[brycealbright]

Thanks SonOfGun, 4Runnerman and BartB, I meant my topic to be establishing seating depth. If I need to seat a bullet by utilizing the ogive as a point of reference, how can I do this accurately. I have Lyman & Dillon seating dies, of the two, is one better than the other.

[PA-Joe]

Where you having problems taking the measurements? What was confusing you? Once you get the measurement then reduce that by 0.01 or 0.02. You don't want the bullet touching the lands.

What you have to remember is that measurement is only good for that one weight and make of bullet. If you change make or weight you have to measure again.

Also as noted the Mag length may limit the OAL. You round has to be able to feed from the Mag. Too long an AOL may result in feeding issue.

[Bart B.]

There's little difference across seating dies. They all will seat bullets very straight if the case is sized straight and the case mouth is smooth and the right diameter for proper bullet grip force.

[PA-Joe]

If you have the Hornady Lock-N-Load O.A.L. gauge you should have a screw on case for your caliber rifle. This will give you the max ogive distance for you chamber. You don't have to worry about OAL. Set your bullets 0.01 or 0.02 shorter than that max distance. Do one or two blanks and check to see that they will manually feed from your MAG.

[Unclenick]

Brycealbright,

I still a little confused. Are you asking how to use the gauge, or are you asking how to establish how far from the throat to seat the bullet? Or are you asking how to get the most precise measurement from the gauge?

[musher]

1. Seat bullets just deep enough to feed reliably from the magazine. That's been the standard for decades. If they're too long for the chamber, whoever chambered the barrel should fix it with no cost to you unless they cautioned you about it.

Only if you'll load rounds one at a time for slow fire, single round loading for rifle competition should you be concerned about seating bullets to ant longer lengths.

Most publishers of load data for semiauto ammo are not smart enough to list overall length as what feeds reliably from magazines. They should also mention there's a few hundredths inch spread in ammo length that ammo will shoot equally accurate in. That's how far the origin of the rifling erodes away every thousand rounds. Are you going to seat bullets a couple thousandths inch less every hundred rounds to keep bullet jump to the rifling distance pretty constant until you consider it worn out? People winning matches and setting records don't.

say what??

Too long to feed through the mag is too long for semi-auto use. Too far out in the lands is also too long. These are independent.

OAL is a saami spec for the cartridge, it doesn't have anything to do with the intelligence of reloading manual authors.

[Metal god]

All advice so far has been spot on . I'd like to ask a question and or add to the questions above .

1) Are you loading from the mag ? if so , see Bart B for answer . I'm not sure but if your loading the lightest gr bullets for 223 . You may want to seat a little deeper then mag length to insure bullet hold . There is a minimum you want to seat a bullet . Some say the diameter of the bullet others say half of that is fine . I'm sure the caliber your loading has something to do with that answer .

2) Are you loading one shot at a time by hand ?

3) What grain/length bullet are you loading ? Are they FB or BT

Questions 2 & 3 kinda go together and as the answer to question 3 changes , so to will the answer .

You say 223 caliber bullet but what matters here is the chamber , are the rifles chambered in 223 Rem or 5.56 NATO ? Using light bullet in a 5.56 chamber , you might not be able to seat the bullet long enough to measure ogive to lands with out the bullet falling out of the case .

[brycealbright]

My friend, Tim, and I set out to measure O.A.L. with two cartridges on two rifles. A Colt and an Anderson AR-15. The bullets, Hornady 22 cal .224, 55 gr FMJ-BT with Cannelure (#2267) the other, Hornady 22 cal .224, 75 gr BTHP (#2279).
Tim worked for some time trying to find the land on the Colt with the 55 gr, we gave up. The bullet kept falling out of the case.
Now for the Alexander, Tim got the measurement of 48.15 three times with the 55 gr bullet.
Next, we went back to the Colt with the 75 gr. We got a measurement of 49.85.
Then, back to the Alexander with the 75 gr and confirmed a measurement of 49.89.
The cartridges are for, as described above, semi-automatics and of course, to fit the applicable magazines. The reason for our frustration, stems from the videos showing how to seat bullets. It seems that most of the demonstrators on YouTube.com don't care about adding or subtracting a thousand of an inch or so when seating a bullet. I do, because I am entering a learning curve,

[Jim243]

We got a measurement of 49.85.

Bryce, there must be some mistake with your measurement!! I use the 75 grain Hornady A-Max's and the L-N-L curved gauge as well and the longest measurement I have obtained was 2.89 inches and that was in a bolt action rifle. Are you using millimeters? The standard length for a 223/5.56 magazine is 2.250 inches or 57.15 millimeters. A 55 grain bullet would normally be set to 2.200 inches or 55.88 millimeters. This is measured from tip of bullet to base of the case. That is how OAL is stated in almost all manuals with load data.

Jim

[Metal god]

OK I have the Hornady 75gr match bullet and some 55gr Win FMJ-BT bullets on hand .

My measurements in a 5.56 chamber are as follows using a L-N-L straight OAL gauge . This test is just using one bullet from each lot . It is not an average of most bullets in each lot

Winchester 55gr FMJ-BT

Bullet length base to tip = .732" / 18.60mm - Base to Ogive .380" / 9.65mm

Max COAL = 2.368" / 60.08mm . From Case head to Ogive = 2.018" / 51.30mm


Hornady 75gr match bullet

Bullet length base to tip = .9920" / 25.20mm - Base to Ogive = .5855" - 14.88mm

Max COAL = 2.396" / 60.86mm - Case Head to Ogive = 1.992" / 50.59mm


Again this was just using one bullet of each in a 5.56 chamber . I did not measure the COAL 5 to 10 time each to get an average so if I were to measure again I'm sure my numbers would differ a tad and yours may a bit as well . These are just some quick numbers for you to look at and compare .

FWIW in a semi auto you do not want the bullet touching the lands . It could hurt function of the firearm . Anything loaded to mag length will fuction fine . If your loading the longer bullets and plan to load one cartridge at a time by hand . I'd seat the bullets at least .005 off the lands and really more like .010 off .

[brycealbright]

To be on the safe side, I have decided to get some private instruction at my gun range. Until that time, I plan to go by the book. Thanks to all for your help and MetalGod, grandchildren are priceless, congratulations.

Happy Holidays,
Bryce

[PA-Joe]

It makes sense that the 55 grain would fall out on the Colt. It has a long throat. So just load per Hornady book. With the 75 grain bullet Mag length is going to be critical.

[olddav]

brycealbright,

I've been giving this some thought myself and the only solution I think would work is to use a bullet comparator. Seat the bullet in the case (do a couple of them) and using the comparator measure the completed rounds from the ogive to the base of the casing. Even then there will be some variations in lengths, but you will at least know how much your dealing with.

In the interest of full disclosure I have no experience or data to support the above statement.

[chiefr]

Bart B. posted: Seat bullets just deep enough to feed reliably from the magazine. That's been the standard for decades.

Yep, absolutely.
Problem solved

[rg1]

To use ammo from an AR magazine the longest overall length is what will feed from the magazine which is 2.260" maximum. The Hornady 55 fmj's recommended oal is 2.200" and best overall lengths for them is 2.200" out to 2.230". I measured 2 AR-15's just for curiosity. Seated to touch the lands in one AR was 2.370" oal and the other was 2.390" with Horn. 55 fmj's. Both lengths the bullet was barely in the case mouth and about to fall out. Now in my one bolt action .223 rifle the overall length to touch the lands was only 2.246" with the Horn. 55 fmj. Your 75 gr. BTHP's are designed to be loaded to mag length also and Hornady recommends 2.250" for them. Now the 75 gr. A-Max is for loading one at a time directly into the chamber and can't be loaded shorter to fit a magazine. Oal's for them is recommended at 2.390" while in my one match AR to touch the lands the oal would be 2.430". With Sierra's 80 gr. Matchking to touch the lands in the same match AR the distance to lands is 2.472". Point is that you can not get close to the lands with any bullet designed to be fed from a magazine. That's just how AR chambers are. You load to fit the magazine and seating longer won't help accuracy to any degree. Bolt action rifles usually do not have this long throat that an AR does.

[bfoosh006]

brycealbright,

Just in case you didn't know.... the freebore / throat on my Colt is VERY long from the factory... so much so that I can single load and shoot factory Fed. 80 SMK without a problem, none of my other four rifles can do that.

All of the manufacturers use different reamers. So I have no idea how much freebore the other rifle has.

Just in case none of you have seen Fed. 80gr ...

Note:WILL NOT WORK IN AR15's.....OAL IS WAAAAYYY OVER SAMMI SPEC>This round is designed for use in single shot, long throated match chambered rifles only. Do not purchase unless you are CERTAIN you have this type of rifle. Not designed for AR15/M4 rifles.




You can easily see in the photo how much longer the bullet is seated out.

[P-990]

I guess I'm unclear of the question. If you're loading magazine length for an AR-15, you don't need an OAL gauge. The 55gr Hornady FMJBTs have a cannelure. Seat these so the case mount is roughly in the middle of the groove, you'll probably end up around 2.20-2.225" from base to tip. The 75gr Hornady HPBT is also a magazine length bullet, you'll end up around 2.25" base to tip.

Side note: you can use the straight OAL gauge in an AR, just shotgun the recievers and pull the BCG. Much easier than the curved model.

Side note 2: when you're seating out to the rifling you want a comparator to go with your OAL gauge. You'll want to recheck your measurements with every new batch of bullets you use. I've always done this for loading 80gr bullets in my match rifle. But there is no way those rounds will fit in the 2.26" window of a standard AR-15 magazine.