C.O.L. seems too long

[dsv424]

I purchased some Hornady .308 150 grain BT-FMJ to load. This bullet has a cannelure on it. The only way to meet the C.O.L. is to make the length .45" shorter than what is called for, so I can get the case mouth in the cannelure. The bullet is #3037 in Hornadys' 7th Edition pg. 447. What am I missing here in order to get what Hornady is asking for? The max case length is 2.015 and this won't achieve what I need to make this right. The only solution I see is to shorten the C.O.L. from 2.780 to between 2.725 and 2.735. This way I can crimp it on the cannelure. Hopefully I'm not seeing the whole picture here because I can't believe Hornady would print something that can't be done.

[Alpo]

First, you're talking about making it .045 shorter, not .45 shorter. BIIIIIG difference.

Now, I don't have a Hornady book, but taking a quick look at the Lee book, for 150 grain bullets in 308 Winchester (I presume you are loading 308 Winchester, although you don't say) they give OALs of from 2.53 up to 2.745. It depends on the powder.

Now, does your book say "Minimum COL", or "Maximum COL", or just "COL"? Exactly how does the book give the requirements.

And, just because it has a cannelure, you do not have to seat it to the cannelure.

[dsv424]

It is Winchester .308 and it states C.O.L. only. Sorry for the misprint I did mean .045. Didn't realize you could seat it away from the cannelure although that would kinda defeat the purpose of the cannelure, although I seat and crimp bullets without a cannelure all the time. Do you think Hornady would state these measurements knowing it would not fall in the cannelure area of the bullet though?

[woolleyworm]

One thing that I do when faced with a head scratching situation is to start back at square one and re-evaluate everything. Rezero my calipers, double check cases, bullets and load data from several sources.

Which powder are you using? and can you post any pics with case and bullet dimensions?

[312shooter]

I'm trying to figure out how you are interpreting data; as long as you do not get under 2.735 or over 2.810 COAL in your situation you will be ok. You will be hard pressed to find a situation were you have a bullet that seats cannelure to mouth and also have an optimum COAL for your chamber (about 2.800) which leads to best accuracy, usally its one or the other. I gather you are shooting a semi auto and want the crimped round, if it's a bolt than I'd forego the cannelure and crimping and find better COAL. I have used the hornady 150's at one point and remember something a little odd about them, I think they were a pretty short with wide ogive and COAL was a mile from the lands of my M1A after seating cannelure to mouth.

[LDBennett]

dsv424:

You have several choice here, depending on whether you are shooting a bolt gun or a semi-auto (lever or pump as well).

For a bolt gun just don't use the cannelure. If you feel you must have a crimp for the bolt gun (???) then use the Lee Factory Crimp Die with any COL that does not exceed 2.810 inches, the Maximum Cartridge Over All length allowed. But whatever COL you choose make sure that the loaded ammo will fit into you gun's magazine. Often even the correct COL will not fit into a gun's magazine. If that COL comes out less than Hornady's recommended COL of 2.780 inches, then the load level needs to be backed down to the starting load and worked up again to the desired level watching out for signs of excessive pressures.

For Semi-auto or pump or lever guns you could just crimp in the groove. If that COL comes out less than Hornady's recommended COL of 2.780 inches for this bullet, then the load level needs to be backed down to the starting load and worked up again to the desired level, watching out for signs of excessive pressures. The Lee Factory Crimp Die works good whether you crimp in the groove or outside of it. The regular crimp from the die set (seating die) should only be used into the crimp cannelure.

For bolt guns I never crimp into the cannelure because I use a COL that puts the bullet only a few thousandths of an inch off the barrel lands, if the magazine length will allow me. I have even modified bolt guns internal magazines to allow the use of longer COL's. The cartridges for each gun are kept separated and only used in that gun and no others. I find that the Max COL is almost always exceeded when I do it this way but the ammo is tailored for only this gun and the specified Max COL is meaningless when the ammo is only for this gun. Using this method often gives very little engagement of the bullet into the case and that means you must handle the ammo with care. If the engagement is too small then I have to compromise on getting the bullet close to the barrel's lands. I suppose the use of the Lee Factory Crimp Die would help make the long rounds less prone to handling problems with small bullet engagements but I have not tried that yet.

For Semi-auto or pump or lever guns I always use the cannelure for a crimp and develop a new load from the starting load level. I develop a load that I know will safely operate in all my guns of that caliber. I use them interchangeably in all my guns of that caliber. But the load level is such that it woks in all those guns safely. I find the Lee Factory Crimp Die the best for these loads.


LDBennett

[dsv424]

Thx for all the advise everyone. The gun is a semi-auto Saiga .308 LD, so I will be adjusting from the starting load level. I assume since I will be crimping in the cannelure which is going to make the O.A.L. shorter it will increase pressure to a certain degree. This is what I was mainly concerned with if I had to do it this way. The powder I'm using is IMR-4064(someone asked so thats why I mention this). My other question was: Why would Hornady state measurements that can't be achieved? Could it be a mistake in the book? Probably need to ask Hornady about this I guess. There seems to be so many varibles that the only way to safely manuveur around them is years of experience and knowledge of what occurs each time you change from what the manufacturer has written. Since I don't have the years under my belt yet I hesitate to try work-arounds. Better to ask the Pro's. Thx again guys!

[LDBennett]

dsv424 asked:

"Why would Hornady state measurements that can't be achieved?"

It is probably that the bullet was developed for a different cartridge other than 308 (perhaps 300 Savage, 30-06, 300 REM Short Action Ultra Magnum???) with a shorter neck. I'd research it except that it is not important based on the info I gave earlier. Anyway the Lee Factory Crimp Die does not need a cannelure to crimp. You can put the bullet wherever you want with that die (not so with a regular crimp that is part of the seating die).

I did look at the 30-06 and I would bet that the bullet was made for it.

For your semi-auto 308 I'd make sure the trim lengths were at the minimum (all the same) and crimp into the cannelure, then work up the loads. If you get the load too light the bolt will not cycle far enough to extract, eject and pickup the next round. The load level that just allows that all the time is the lowest load level you can use. I might step it up another grain from there for IMR4064 to be assured the gun will work in all weather and temperatures but never above the listed Maximum load. Another test if the gun has a "lock open on the last round" feature would be to load one round in the magazine, close the bolt, and fire it. The load that successfully locks the bolt back every time is the minimal load. Again step it up about one grain of IMR4064. If you overload the ammo it will beatup the gun terribly and mess up the gun's timing, dumping gas in your face. NOT GOOD! Don't ask how I know that!

LDBennett

[fprefect]

Originally Posted by dsv424

I purchased some Hornady .308 150 grain BT-FMJ to load. This bullet has a cannelure on it. The only way to meet the C.O.L. is to make the length .45" shorter than what is called for, so I can get the case mouth in the cannelure. The bullet is #3037 in Hornadys' 7th Edition pg. 447. What am I missing here in order to get what Hornady is asking for? The max case length is 2.015 and this won't achieve what I need to make this right. The only solution I see is to shorten the C.O.L. from 2.780 to between 2.725 and 2.735. This way I can crimp it on the cannelure. Hopefully I'm not seeing the whole picture here because I can't believe Hornady would print something that can't be done.

C.O.L. is really a meaningless term as it will vary from rifle to rifle depending upon the magazine size, (if you intend to use the magazine) and if you are after the maximum in accuracy it will differ from bullet to bullet, in this case the max. C.O.L. being the length of a loaded round when the bullet ogive is in light contact with the rifling lands. In the later case, should it be your desire to achieve this C.O.L. you will want the bullet to be seated deeply enough into the case to prevent it from easily becoming lose and falling out when handling and loading the ammunition.

So basically the C.O.L. is an oft used term that is really meaningless unless you are discussing one particular rifle shooting one particular bullet and will change if either of the above changes.

For hunting purposes where more than one shot may be needed, the rounds should be loaded to a length to easily fit into the magazine. For maximum accuracy, if possible, the bullet should be seated to a point where it just touches or is within .005 of an inch from the lands. Just ignore the cannelure.

F. Prefect

[LDBennett]

The COL is not meaningless when it appears in a load table of reloading manual. It is the COL used to develop the data presented. The Max COL is the industry standard for the Maximum COL and if exceeded you may end up with ammo that won't fit in some guns.

When you pull the bullet out to reach the barrel lands to within 0.005 inches, the resultant pressure and velocities in the gun used to develop the data will not be met. Admittedly, your gun might not meet the data or might even exceed the data when used in your gun as all guns are different, even if it is the same brand and model gun and reloading recipe. What the data gives you is a much better chance that if you follow the recipe including the COL given, you will be loading to safe levels if you start at the starting load.

Puling the bullet out to within 0.005 inches of touching the barrel's lands is an advanced loading technique and unless you have the know how and the tools I most certainly suggest it not be done. In the original posters case, I still suggest he crimp in the cannelure (it is a semi-auto gun that bangs the ammo around a lot!) and start load development at the starting load or a grain below.

Reloading data is not to be taken lightly if safety is to be paramount. When a reloader gets a bunch of experience and is well educated as to reloading then and only then should he try any advance reloading techniques, in my opinion. But everybody gets to choose. In my earlier days I was a bit loose on following the manuals. A couple of "accidents" (no damage to me or my guns, fortunately) from that attitude got my attention and safety is now the first order of the day.

LDBennett

[dsv424]

I didn't think of the fact that this bullet was designed for a different caliber, but it does make sense now. In fact, it does appear that it would be better suited in a 30-06 case. I have all my cases trimmed to 2.008 which is just slightly above to minimum trim length.(2.005 min. trim length) My gun does not lock open on the last round. I have never loaded a case above the half way range anyway. I have always been satisfied with my results from min. to half way. Don't have my book in front of me now but I think the min for IMR-4064 was about 39 grains so I'll probably be trying about 39.8 to 41.8 to test with. I haven't any cycling problems with this gun in any of the recipes I have made for it so far and I have about 15 different ones now. Thx again LD.

[fprefect]

Originally Posted by LDBennett

The COL is not meaningless when it appears in a load table of reloading manual. It is the COL used to develop the data presented. The Max COL is the industry standard for the Maximum COL and if exceeded you may end up with ammo that won't fit in some guns.

When you pull the bullet out to reach the barrel lands to within 0.005 inches, the resultant pressure and velocities in the gun used to develop the data will not be met. Admittedly, your gun might not meet the data or might even exceed the data when used in your gun as all guns are different, even if it is the same brand and model gun and reloading recipe. What the data gives you is a much better chance that if you follow the recipe including the COL given, you will be loading to safe levels if you start at the starting load.

Puling the bullet out to within 0.005 inches of touching the barrel's lands is an advanced loading technique and unless you have the know how and the tools I most certainly suggest it not be done. In the original posters case, I still suggest he crimp in the cannelure (it is a semi-auto gun that bangs the ammo around a lot!) and start load development at the starting load or a grain below.

Reloading data is not to be taken lightly if safety is to be paramount. When a reloader gets a bunch of experience and is well educated as to reloading then and only then should he try any advance reloading techniques, in my opinion. But everybody gets to choose. In my earlier days I was a bit loose on following the manuals. A couple of "accidents" (no damage to me or my guns, fortunately) from that attitude got my attention and safety is now the first order of the day.

LDBennett

You are correct. I'm a competitive benchrest shooter and sometimes forget that some reloaders are not always familiar with the higher pressures that can come from seating a bullet with little or no freebore, which is the first place most accuracy shooters will try with any new load or bullet. I should have advised reloaders to start with moderate loads and carefully increase charge weights as needed to achieve the best possible accuracy, if that is the goal they are attempting to achieve as opposed to producing the best hunting load.

F. Prefect

[steve4102]

From Accurate Powders web site.

SPECIAL NOTE ON CARTRIDGE OVERALL LENGTH “COL”
It is important to note that the SAAMI “COL” values are for the firearms and ammunition manufacturers industry and must
be seen as a guideline only.
The individual reloader is free to adjust this dimension to suit their particular firearm-component-weapon combination.
This parameter is determined by various dimensions such as 1) magazine length (space), 2) freebore-lead dimensions of
the barrel, 3) ogive or profile of the projectile and 4) position of cannelure or crimp groove.


From Hornady #7.

[LDBennett]

steve4102:

No argument. You are exactly right but......

The last thing a new reloader needs is a bunch of variables to the reloading that may get him or her in trouble. I always recommend using the recipes in the manuals exactly as written for newbies. That way success is almost guaranteed. What a way to ruin a future reloader's day than for them to unknowingly do something that will create a high pressure situation and hurt themselves and/or the gun.

It takes special tooling and technique to put the bullet just off the barrel lands. If you get the cartridge OAL too long it will jam into the the lands. That can create very high pressures. It also can pull the bullet if a loaded cartridge has to be removed from the gun for any reason. Get the cartridge OAL too short and there go the high pressures again. Using a cartridge OAL different than the one recommended in the reloading manual is an advanced reloading process and should not be attempted until reloading is thoroughly understood and the right tools are at hand.

Safety first!

I indeed tailor the cartridge OAL to each bolt gun but use the referenced cartridge OAL for semi-autos, levers, and pumps. I started reloading in the 1960's and reacquired the hobby in full force almost 25 years ago. You may also be seasoned but I think the poster is not, based on the way the question was asked (???).

LDBennett

[Alpo]

Originally Posted by LDBennett

steve4102:


It takes special tooling and technique to put the bullet just off the barrel lands. If you get the cartridge OAL too long it will jam into the the lands. That can create very high pressures. It also can pull the bullet if a loaded cartridge has to be removed from the gun for any reason.

LDBennett

I've got two alg rifles. 9.3x57. A Husqvarna 96 Mauser and an FN 98. Got the Husky about three months earlier than the FN. The ammo for the Husky shot fine. Tried some in the FN and it kicked the snot out of me. Fired two rounds, and decided something was wrong. Pulled the bolt back, to unload the third round, and powder went everywhere. Pulled the case off the bullet. Bullet stuck in the rifling. Now, this stuff was loaded to the manual's OAL, so apparently my FN has a short chamber. With no lead at all, it's a wonder nothing went BOOM. So I need to seat my bullets deeper, which means a lighter powder charge.

[LDBennett]

Alpo:

I assume you are talking surplus military guns (??)

These kind of guns have been to who knows where and modified by who knows whom. The chances are the chamber is not reamed correctly. But if the headspace is OK then you can indeed set the bullet back in the case to allow some freebore. But do download them a bit, and start at the starting load if you have to seat them very deeply.

I have a few of these surplus "jewels" and I think I'll not be having any more. Between shot out bores, excessive headspace, oversized chambers, they are no longer worth buying for me. I have stories!

But I did have a new Browning BAR that missed the finish reaming and the bullet would stick in the sharp ends of the lands. It fired OK and the pressures didn't seem excessive but on occasion it would not fully close the bolt and the bullet would stick hard in the lands. The cartridges didn't loose their bullet but it took two hands to open the bolt (using a wood stick on the bolt handle, resting the gun butt on my body). The frustration was getting the Browning Service Station to agree there was a problem and it was Browning's duty to fix it. I finally found the lands sticking up sharp, pointed it out to the gunsmith at the station, and he just threw his hands in the air and said he'd didn't see the problem but he would send it to Browning. When it returned the problem was visibly fixed and it is fine now.

LDBennett

[Alpo]

Originally Posted by LDBennett

Alpo:

I assume you are talking surplus military guns (??)

LDBennett

Nope. Commercial guns. The Husky was made in '36, for use in-country. Got it a few years back when Sarco got in all them Swedish guns. Got it and a 22 and five underlever doubles. Sarco got a big chunk of my paycheck, for a while.

The FN is a custom gun. Made in the late 50s, with a new, commercial action.

Weren't too many military surplus guns around in 9.3mm.