Determining OAL

[Expatmedic]

Ok, so I am still learning about loading for my 6.5 Creedmoor. I am loading to COAL. A friend said you need to buy these things and that will help you "a lot". But I really do not know what I am doing when it comes to this. I am shooting 5 shot dime sized groups at 100, but from what I have read and gleaned from the interwebz I can do better. I am still learning proper vernacular.

These are they. If you all would not mind explaining it to me like I am 5 that would really help me out.

Thank you.

http://www.hornady.com/store/Lock-N-Load-OAL-Gauge-Straight-1Each/

http://www.hornady.com/store/Lock-N-Load-Comparator-Set-Body-and-14-Bullet-Inserts-1-Each/

 

[PA-Joe]

Are you reloading now and getting the dime groups?

Using the sizing die and setting the shoulder of the case back too much reduces the number of times you can reload the case.

Using the seating die and setting the bullet back too much will effect accuracy. Those tools are used to see if you are seating the bullet too much or too long.

The tools work.

Hornady also has bushing to check how much you are setting the shoulders back.

 

[dahermit]

Ok, so I am still learning about loading for my 6.5 Creedmoor. I am loading to COAL.

It is not clear what you mean. Do you mean that you are loading your cartridges to the over all length as suggested in one of the loading manuals?

A friend said you need to buy these things and that will help you "a lot". But I really do not know what I am doing when it comes to this. I am shooting 5 shot dime sized groups at 100, but from what I have read and gleaned from the interwebz I can do better. I am still learning proper vernacular.

These are they. If you all would not mind explaining it to me like I am 5 that would really help me out.

The links you posted are for measuring the maximum overall length possible for your rifle's chamber. The device uses a brass case that has had the rear end drilled out and threaded to take a "stick" that screws into the end and pushes a bullet into the lands of the rifle. Then the "stick" is locked into place and the case with the bullet is removed from your chamber and a small piece of metal (the second site you listed...you will need one for 6.5MM.), that will fit on your bullet will be used to determine the maximum length from the base of a case to the ogive (where the bullet's shape changes from parallel sides and begins to curve towards the nose), of the bullet. You measure that distance with a dial caliper. That length is the maximum length of your loaded cartridges from the end to ogive of your rounds. You then would use that length to experiment how far of the rifle's lands you want your handloads to be. Have no fear...the device for measuring for cartridge overall length, comes with instructions and a diagram. A verbal description of the process, as you have likely noticed by now, is really difficult to understand. If you think you want to experiment with O.A.L. to find you best accuracy, order the tool and follow their instructions. Some people find the best accuracy with the bullet short of touching the lands of about .020 or so. Some closer, some further away.

 

[Don Fischer]

I don't know what those tools cost but they are not necessary. That measurement can be easily determined with a dial caliper and a cleaning rod. Remove your bolt and drop a bullet into the chamber. Insert a wood pencil in behind it to hold the bullet. Take a patch jag an cut it off so that when you put it in the rod it close's the threaded end and makes the rod flat on the end. Holding the bullet with the pencil, slide the rod into the barrel until it meet's the bullet. Mark that spot on the rod at the muzzle. Remove the bullet and put the bolt back in and slide the rod down until it touch's the bolt face and again mark the rod at the muzzle with a pencil. Pull the rod out and measure between the marks. That will be the overall length with the bullet touching the land. To figure out how far off the lands you are, seat a bullet into the case to that measurement and then just a bit more until your just off the lands. If you reduce the OLL by .020, you'll move the bullet back off the lands .020. The distance between the point of the bullet and the ogive won't change so by moving the tip .020 you actually move the ogive .020.

No, If your shooting dime sized groups and this is a hunting rifle, you don't need any better than you have. Getting on below that size group's is gonna come in very small step's if at all with stuff that may only improve accuracy a couple thousand's at a time, for me, they are not worth chasing. If your going to shoot competitively, you'll probably need to do a lot of ork on the rifle, expensive work, just to have a rifle that can compete.

 

[dahermit]

I don't know what those tools cost but they are not necessary. That measurement can be easily determined with a dial caliper and a cleaning rod. Remove your bolt and drop a bullet into the chamber. Insert a wood pencil in behind it to hold the bullet. Take a patch jag an cut it off so that when you put it in the rod it close's the threaded end and makes the rod flat on the end. Holding the bullet with the pencil, slide the rod into the barrel until it meet's the bullet. Mark that spot on the rod at the muzzle. Remove the bullet and put the bolt back in and slide the rod down until it touch's the bolt face and again mark the rod at the muzzle with a pencil. Pull the rod out and measure between the marks. That will be the overall length with the bullet touching the land. To figure out how far off the lands you are, seat a bullet into the case to that measurement and then just a bit more until your just off the lands. If you reduce the OLL by .020, you'll move the bullet back off the lands .020. The distance between the point of the bullet and the ogive won't change so by moving the tip .020 you actually move the ogive .020.

The only difference between using that O.A.L. tool and the cleaning rod method (I have done both), is that the cleaning rod method gauges off the nose of the bullet which, especially in hollow point target bullets is imprecise (measure some and see), where as the tool uses a place on the ogive to measure, which is not dependent upon the bullets having uniform points.

 

[rsnell]

If you are already shooting dime size groups with a hunting rifle, you do not need this measurement. I have used a Sinclair bullet seating depth gauge for 25 years to determine the overall length for bolt action rifles. It can be purchased from Brownells for $23.99 and the catalog number is 749-004-650WS. It is not necessary to purchase a bullet seating depth guide for each rifle.

I use it for 22-250, 270, 7mm-08, 30-30, 308, and 30-06. Manufactures of the rifles are Ruger, Remington, Winchester, and Savage.

 

[dahermit]

If you are already shooting dime size groups with a hunting rifle, you do not need this measurement.

If he is shooting a target rifle or hunting rifle has not been determined:

Ok, so I am still learning about loading for my 6.5 Creedmoor.

Even if he is shooting a Target Rifle, I agree and that he really would likely get more (potential improvement in accuracy), if he would spend his money on a cartridge run-out measuring device instead: http://www.ebay.com/itm/Hornady-Lock-N-Load-Ammo-Concentricity-Tool-050076-/311738008386?hash=item4895088342:g:~igAAOSwx2dYI-6n

 

[44 AMP]

I am shooting 5 shot dime sized groups at 100, but from what I have read and gleaned from the interwebz I can do better. I am still learning proper vernacular.

If you all would not mind explaining it to me like I am 5 that would really help me out.

I just measured a dime from my pocket and its approximately .7" across. That would be 3/4" MOA (minute of angle) at 100 yards. Most of us would consider that excellent for anything other than benchrest shooting competitions.

What rifle are you shooting? Iron sights or optics??

Contrary to what one often sees on the interweb, not every rifle (and not every shooter) is capable of better than that.

Generations of shooters considered a rifle that would shoot 1 MOA to be a goal to be worked for, and if they actually got it, or better, in a field rifle, it as a thing of great value.

Two questions you need to ask,
Is your rifle capable of better than .7" groups?
Are you??

Neither is a given.

A friend said you need to buy these things and that will help you "a lot".

Does your friend use them? Could you borrow his?? get him to show you how they will help?

Personally if I were getting .7" groups I wouldn't waste my money on any new tools or gauges. There is absolutely a point of diminishing returns, and you might spend a lot of money for very little, or no gain.

 

[RC20]

I don't know what those tools cost but they are not necessary

Dom Fisher:

I would amend that to you can do it without it but look at the time and effort you have gone to, not to mention you need to hit the bullet square putting your rod down the bore vs a very quick and reliable other approach.

And that does not give you an Ogive measurement, its COAL.

Tips vary a lot, Ogive is much closer.

So the bushings/adaptors that go onto your Hornady Comparator (micrometer blade device) work well.

It also works as part of the shoulder bump back.

All in all its a low cost very good tool and well worth it for anyone interesting in punching the smallest group of holes possible.

 

[Unclenick]

Here are some match bullets I measured one time. The bullet base-to-ogive varies a maximum of 0.008", while the tips vary 0.0135". It's due to bullets off different tooling sets being mixed before they are boxed. The ogive is the better of the two, but neither is anything to write home about. What makes the ogive the better measurement is that's what most seating dies push down on and it's what touches the lands, and making those two points work together is good.

Using the seating die and setting the bullet back too much will effect accuracy.

Ans so can setting it too far forward. Item 3 of this article is an example. This article in Berger Tech Talk is more detailed and includes other examples.

 

[Don Fischer]

The ogive of the bullet never changes. When you push the bullet in with the pencil, the cleaning rod does measure to the tip of the bullet. You need to use that same bullet in a work up dummy, because the ogive to the tip does change a bit. Doesn't matter unless you simply wan the measurement to the ogive. When you reach this point with either method, your gonna want to get the ogive off the lands. What I do is seat a bullet the the length I got, same bullet. Then chamber and you will feel the ogive touch the lands. Start screwing the bullet seating die in about 1/8th turn and each time run the same case and bullet into the die. Check it again. Once your off the lands, set your seating die right there and leave it locked their. Again, the length from the bolt face to the ogive will never change. To get the same exact measurement you get with that tool, measure the length before you start setting the bullet deeper to clear the lands. Once your there, Simply subtract the short measurement from the long one and you have the length to the ogive from the bolt face to the ogive, tell's you just how far back you have seated the bullet. On that same bullet, the distance from the ogive to the tip of the bullet will never change. Very simple and not hard to do at all. I seat everything just off the lands, I don't care how many thousands of an inch it is. Remember the bolt face to the ogive never changes and the ogive to that bullet tip never changes. The OLL of a spitzer, hollow point, round nose ect, won't ever change.

Just read Unclenick. Exactly right!

 

[cw308]

Expatmedic
I have both tools. The OAL Gauge helps you find how far you can seat the bullet until it hits the rifling. So you can jump or jam your rounds, some rifles shoot better with a little jump to the rifling to touching or jamming into the rifling to the ogive of the bullet ( taper )
The comparator measures the sized bullet length to the ogive. I found the RCBS Precision Mic the best & the easiest for that measurement & case headspace measurements.
The 6.5 CM is a nice round, what rifle do you have & are you using it for hunting or target shooting ? Hope I helped Chris

 

[Stats Shooter]

Personally if I were getting .7" groups I wouldn't waste my money on any new tools or gauges. There is absolutely a point of diminishing returns, and you might spend a lot of money for very little, or no gain.

Some pearls of wisdom in that statement. I have semi-recently gotten into competitive shooting. The minimum level of accuracy needed to be competitive is 0.5" or 1/2 MOA. A decent handloader with a single stage press, trimmer, scale, set of calipers, and patience can put together a 1 MOA load that will ring steel at long range or put meat in the freezer provided the rifle and shooter are up to it. ...And when I say 1 moa I mean consistently 1" at 100 yards, not 1 in 5 groups 1 moa while the rest are 1.5 moa. I mean always.

Going from 1 moa consistently to 0.5 takes all the cost, time, and effort and multiplies it by 10. Not to mention the quality of rifle and shooter. Then going from .5 moa to 1/4 redoubles all the cost, time, effort etc.

I currently have 1 rifle capable of 1/4 MOA...The barrel alone cost $600. I'm not saying you can't do better, but once you hit sub moa, the 10/90 rule goes into effect, Which is that a 10% improvement requires 90% more money and effort.

 

[Don Fischer]

That's interesting. I guess you are shooting steel, I've never done competitive shooting other than indoor rim fire. If he was shooting 100yd benchrest, a 1/4" rifle would not have much chance of finishing in the top 20 or so I've read. Lot of guy's talk of little reloading tricks to get better accuracy from their hunting rifle's. Some of those tricks may gain them .005" smaller dia group. Problem is none of the hunters I know of has the ability to measure such small group's. I have one 1/2" rifle. Rem mod 700 in 6.5-06 with a Shilen match barrel. Deal is the only I can get it donw there and keep it there is by shooting SMK's.

 

[Stats Shooter]

That's interesting. I guess you are shooting steel, I've never done competitive shooting other than indoor rim fire. If he was shooting 100yd benchrest, a 1/4" rifle would not have much chance of finishing in the top 20 or so I've read.

F-CLASS open LR (1000 yards). I was shooting mid-range F-TR 600yards with a .308 but that rifle is 1/2-3/4 moa with 175 gr smk's. My new open rifle (300wm) is grouping 1/2 - 3/8" at 200 yards so far within a band of 78-79 gr of Hodgdon H1000 and Hornady ELD 225 bullets. Details are in some other threads I posted but it seems 2850-2900 fps is the sweet spot. I had to buy quick load to find out but the guy on the phone said I was achieving that at almost 60000 psi.

But I digress, no I'm not shooting BR...If I was, 1/4-3/8 moa wouldnt be competitive.

 

[T. O'Heir]

An Ogive measurement means nothing. OAL is measured from the pointy part to the flat part with no ogives involved. SAAMI OAL specs, that all U.S. ammo manufacturers and reloading companies work from, are from the pointy part to the flat part. Ogive isn't mentioned at all. Anywhere, ever.
The ogive is about the off-the-lands stuff that has no standard and is unnecessary.
"...a rifle that would shoot 1 MOA..." A commercial hunting rifle that consistently shoots 1 MOA out of the box with any ammo is a miraculous thing.
The Hornady tools are designed for one thing. Separating you from your money. So are cartridge headspace gauges. Cartridges do not have headspace. So are most of the other assorted "tools". Buy a digital Vernier calipre. That's all you need.

 

[F. Guffey]

I am shooting 5 shot dime sized groups at 100, but from what I have read and gleaned from the interwebz I can do better.

And then you are loading to COAL? 'overall is one word so we are talking about COL as in case overall length; and then the part no one includes. That would be 'maximum', that puts it sounding like 'maximum' case overall length.

Maximum overall case length can put the bullet and case too long to feed from or the bullet hits the rifling before the bolt can close.

Now? Do you need the tool? I do not know but: I don't. I drill out the primer pocket/flash hole of the case and then sized the case for the chamber and then seat a bullet.

After seating a bullet I chamber the test case and then use a cleaning rod to push the bullet out of the case until the bullet contacts the rifling. Once the bullet contacts the rifling I stop pushing. I remove the test case and then place it in the shell holder and raise the ram with the seating die screwed into the press 'loosely'. And then I raise the ram and adjust the seating die to the case without a crimp; and then? I adjust the seating plug down to the bullet, once the seating plug contacts the bullet.

Once the seating plug contacts the bullet it is said the seating die is adjusted to .ZERO' off the lands. I know, that makes no sense, but if I want to seat the bullet .030" off the lands I use a depth micrometer to lower the seating plug .030".

I have the Hornady tool, I do not use it but I have it just in case, I also have 7 cases for different chambers that fit the tool, I do not use them but I have them just in case. If I needed a comparator I would make one, the difference between my home made comparator and the store bought one is the datum/round hole/ circle. MY round hole/circle/datum would be exact; everything else has a bevel.

F. Guffey

 

[RC20]

T. O'Heir


Again I will disagree.

While the various tools may not be your cup of tea, it does not means its no ones.

Ogive and the others may be a relative thing, but once you know what your bullet Ogive is for a given rifle, then you can reasonably repeat the seating depth of the bullet and yes that makes a difference if you are going to accuracy.

My estimate how much better for the Ogive was .005, so not to far off from Unclcenicks data (and thank you, very nicely done chart and great data)

Once I got one I would do all of them another .005 further out as a starting point (low to mid level loads)

I also disagree on head space gauge.

I was assessing Model of 1917s and got enough data base to know that the head space was out at the filed reject range for a normal barrel.

I could use a Shoulder measurement to do the same thing, but that's another one of those useless tools.

I can tell you that the rounds for those guns should be separated out from the Shilen barrel gun which is much tighter.



I don't regret the gauge buys, the next rifle I am going to build without those but I will be recreated the equivalent with new, fired and tape on back new and fired cases.

 

[Stats Shooter]

Again I will disagree.

Its a relative thing, but once you know what your bullet Ogive is for a given rifle, then you can reasonably repeat the seating depth of the bullet.

My estimate how much better for the Ogive was .005, so not to far off from Unclcenicks data (and thank you, very nice3ly done chart and great data)

Once I got one I would do all of them another .005 further out as a starting point (low to mid level loads)

I also disagree on head space gauge.

I was assessing Model of 1917s and got enough data base to know that the head space was out at the filed reject range for a normal barrel.

I could use a Shoulder measurement to do the same thing, but that's another one of those useless tools.

I can tell you that the rounds for those guns should be separated out from the Shilen barrel gun which is much tighter.

So, while it may not be your cup of tea, it does not means its no ones.

I don't regret the gauge buys, the next rifle I am going to build without those but I will be recreated the equivalent with new, fired and tape on back new and fired cases

I agree with what RC20 said. I used to use COL (that one's for you Guffey). But just like everyone else found, COL was different for 5/10 bullets. ESPECIALLY polymer tipped bullets. With respect to down range ballistics, it is irrelevant, but with respect to getting consistent chamber measurements, and seating depth consistency it is a big frigging difference!

I only use COL to see if it will feed from the magazine, otherwise COL is meaningless. The only thing that matters in terms of consistency and pressure is the jump or jam, and how close to exact you can maintain that jump or jam. And the most consistent way to measure that is....da da dahhh. Cartridge Base To Ogive or CBTO in the lingo

 

[F. Guffey]

But just like everyone else found, COL was different for 5/10 bullets. ESPECIALLY polymer tipped bullets. In with respect to down range ballistics, it is irrelevant, but with respect to getting consistent chamber measurements, and seating depth consistency it is a big frigging difference!

Just like everyone else found? I do not mind starting over so I will. I drill out the flash hole/primer pocket, I size the case and then I seat a bullet. (STOP) I am the only one that understand the diameter of the rifling, everyone else should make a test case/transfer for every bullet they load for. A reloader can be happy with the length of the case from the top of the bullet to the case head or they can be happy with the distance from the rifling to the case head. After that it gets complicated because there is that thing about seating to, at or into the rifling.

F. Guffey