COL- interesting info from Western Powders

I know there has been a lot of debate here lately about COL. I just found this on Western powders site regarding this topic. It is interesting and actually supports what I have posted here before. Take from it what you want.


the barrel, 3) ogive or profile of the projectile and 4) position of cannelure or crimp groove.


http://www.accuratepowder.com/data/Acc%20Guide%20v3.3%20version.pdf

To represent things in the proper light of the topic, I think the discussion went more like "Don't do it arbitrarily without regard to powder charge."

This is a misrepresentation of the original discussion and is meant to take advantage of the fact that the other individual isn't here to defend themselves.

Both cowardly and dishonest. I think that will shine through though and folks will not be mislead.

The fact that you have posted this irresponsible thread PROVES the other person's perceived opinion of you. You just can't be told you are wrong and humbly take it.

Reminds me of a line from a movie, Toy Story: "You are a sad, sorry little man and you have my pitty!"

From Alliant's Reloading Guide:

A. Prevent deeply seated bullets.
1.Your assembled cartridges must be as long as, or longer than, the minimum length listed for the combination you are reloading.
2.Set your bullet station accordingly and lock tool securely.
3.Keep bullet station clean of accumulating lead and grease.
4.Inspect all loaded rounds for overall length.
5.Be sure every bullet is held tightly by shell mouth, especially pistol loads (recoil drives magazine against bullet noses of contained cartridges).

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Article from M.L McPherson:

Deep Seating

First, seat bullets deeper and roll a gentle crimp over the ogive or driving band instead of into the crimping groove. You will need to reduce powder charge accordingly. Several years ago, I did a piece on this for Handloader's Digest, wherein I developed a table including corrections for every bore size and charge level. Quite boring. For most readers here I can simply suggest the basis of that table and let them do their own figuring.

Measure the percentage change in usable case capacity between load with deep-seated bullet and load with regularly seated bullet, then reduce charge precisely 3/4 of that percentage – e.g., if deep seating the bullet reduces usable capacity (volume under seated bullet) from 10 grains of water to 8 grains of water, percentage reduction is 20%. If, in standard load, correct charge is 5 grains of powder, correct charge in deep-seated load will be about 4.2 grains (20% x ¾ = 15%, 15% of 5 is 0.75, 5 – 0.75 = 4.25). This correction will be very close to ideal.
For those with a chronograph, to match pressure in both loads, look for a percentage velocity difference equal to 1/5 the percentage difference in usable capacity (with both cast and swaged bullets, peak pressure is basis of accuracy). Again, consider our example, if the full-length load launches bullet at 1000 fps, shorter version will generate same peak pressure when it launches bullet at about 960 fps (1/5 x 20% = 4%, 4% of 1000 = 40, 1000 – 40 = 960). Unless volume difference becomes unusually large, perhaps >33%, these corrections will hold with sufficient accuracy for the purpose.

Advantages of deep seating are legion. First, this approach provides for significantly greater bullet pull, which retards initial bullet movement and improves shot-to-shot ignition consistency. Second, more of charge will burn before bullet base clears case mouth and subsequently barrel-cylinder gap, which makes for a cleaner load. Third, with less unused boiler room, primer will do a better job of igniting charge, which improves consistency. Fourth, charge will more nearly fill boiler room, which can significantly reduce powder position effect – see below. Finally, bullet will move further before clearing cylinder, so that more energy will have been imparted into bullet before venting begins – for various reasons, this improves ballistic uniformity.

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William C. Davis, Jr. says –

“It is obviously possible also to increase the free run simply by seating the bullet more deeply in the case. That has two effects on chamber pressure, which are in opposite directions. The increased free run tends to decrease pressure, but the decrease in powder space increases the loading density, which tends to increase pressure. Which effect will predominate depends on the characteristics of the particular load and gun. In most full-charge loads, it is found that the pressure decreases at first as the bullet is seated farther away from the lands, but beyond some particular seating depth, the pressure begins to rise again as the powder space is further reduced. In revolvers, the free run through the cylinder is always relatively great, and increased seating depth always increases the chamber pressures.”

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The following is a rather long and boring narrative on the subject and pertains to rifle cartridges only but there is still some useful information for the reloader in it pertaining to seating depth and pressure:
p.s.It is from the University of Michigan, same state of ........
http://deepblue.lib.umich.edu/bitstream/2027.42/3866/4/bac6873.0001.001.txt

Tell Sackett said:

To represent things in the proper light of the topic, I think the discussion went more like "Don't do it arbitrarily without regard to powder charge."

This is a misrepresentation of the original discussion and is meant to take advantage of the fact that the other individual isn't here to defend themselves.

Both cowardly and dishonest. I think that will shine through though and folks will not be mislead.

The fact that you have posted this irresponsible thread PROVES the other person's perceived opinion of you. You just can't be told you are wrong and humbly take it.

Reminds me of a line from a movie, Toy Story: "You are a sad, sorry little man and you have my pitty!"

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Tell Sackett, I am not sure to whom you direct this statement. Maybe I missed something along the way.

If for G4F, I know he has maintained for quite awhile that COL given in reloading manuals are a guide only. Useful? Yes, but a guide only. He also stated that this is so.

I know I don't follow that COL recommended in my reloading manual to the letter because in my semi 45 acp, they are too long. Won't work in the magazine. So, I have to seat them deeper. However, I do reduce the powder charge a tad.

To use the term "Cowardly and Dishonest", generically, like you did is wrong. You shud pinpoint the person with whom you take issue.

Then let's have a learning discussion.

Take from it what you want.

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I pretty much got the same from "it" that Tell Sackett did.

For those that didn't read the "rest of the story", go back and make sure you pay particular attention to the shaded area. While using published, lawyerfied data, and following the cautions that were given, but not repeated, about reducing loads, working up slowly and watching for signs of overpressure you can make adjustments for OAL. But that doesn't mean OAL isn't a concern, too many people will take unverified data off the internet, toss it into a mixture of substituted components and make themselves a self destruct button. OAL is a concern, just how much of a concern depends on the individual.

Tell, I could feel my blood pressure go back down while reading your first post, thanks and 'good job'.

Now that my suspicions have been confirmed, where's that ingnore button?

Very well put Tell!

COL is a dimension not to be trifled with. From my own experience, I loaded some 9mm 115 gr over 5.6 gr of Unique. The Lyman #49 manual lists 5.8 gr as the maximum for this bullet. I loaded my 5.6 gr loads with the recommended COL of 1.090 and found that my primers were flat and somewhat cratered. I repeated the loading with the COL opened to 1.10. The rounds still feed reliably in both my Kimber Aegis 2 and my S&W 669 however, the primers are no longer cratered. Yes, I do think there is some "wiggle room" but it is not at the top end. The place to experiment with seating depth is with starting loads and not with maximum loads.

Thanks for your clarification as I am sure it will help the new reloaders out there.

Frank

Of all the great forums on this S&W sight, the Reloading Forum seems to have gotten to be the most contentious. In past posts, on this same topic, Lee laid down the law, and, it seems that again incivility is the rule of the day. If you folks have a point to make...make it, but to call someone (regardless of who the insults are aimed at) "dishonest and cowardly" shows no concern for diplomatic "public" discourse, is socially in bad taste, does nothing to promote the real reason that we are here...to share, to "discuss", and to learn, and does not honor the stature of this sight, or the goals (and the rules) of this sights owner!!! This kind of "friction" detracts from the enjoyment factor of this forum, and does nothing to "assist" reloaders!!! I have retired from other forums on the web because of this same issue, and, I have seen other forums "fail" because of the lack of participation by those who had the "experience", who were constantly degraded by insults..............Lets all take a step backwards, cool down, and regroup. When somebody makes a comment or suggestion on this forum, the "reader/reloader" should be the final judge as to what is correct for his particular needs. Readers of these posts should understand that "opinions" are nothing more than that. The "reader" of any post needs to "think" about what is posted here, research the topic for themselves, and come to their own conclusions. What may be correct for one application or need may not be right for another! Remember, its you that in the end pulls the trigger! SAFETY FIRST!

Clarification

Calaveras,
You have brought out my point to the "inth" and with you sir, I cordially agree. To speak to the point and not bring out the reduction of charges if OAL is shortened is almost diabolical, in my opinion. It shows a total lack of concern for the "newbie" reloader.

Thank you for your caution about civility as well as flat top's.

I will stand by my statements in this thread because of the potential of personal injury, not mine but those that are fledglings amongst us.

Let me be perfectly clear:
"Adjusting OAL for fit and/or function is something that needs to be done. What good does it do to have ammo that won't work? It doesn't. My point on this matter is this, don't do it ignorantly. If you have to shorten the OAL for any recipe, feel free, only do it with knowledge, reduce the charge. If you want to lengthen the OAL feel free, only do it with knowledge, you MAY be able to increase the charge weight, READ MAY BE, depending on a myriad of factors. It is my humble opinion to portray this in any other manner is dangerous, disingenuous and showing a total disregard for other people's safety."

Jelly, Frank, you folks are awesome!

Page 7 of http://www.lapua.com/fileadmin/user_upload/esitteet/VihtavuoriInternationalReloguide2009.pdf

* You must absolutely follow the given cartridge overall
lengths (C.O.L.) according to the reloading tables. The change
in the bullet seating depth has a significant influence on the
cartridge pressure.

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(Emphasis added by Tell)

Seems to me theres a horse here, beat to hamburger.

Any experienced reloader knows the repercussions of shortening COL without reducing loads.

And, inexperienced reloaders ask the appropriate questions, and/or do the research to find how to safely shorten COL. If they don't do their part to reload safely and knowledgeably then whos fault is it?

Tell; I think that one good thought to always keep in mind, is that we all speak from our own sphere of experience. For almost 50 years I have been involved in competitive shooting, custom and competition firearms modifications and development, including the fabrication of firearms actions and trigger assemblies, have developed an entire line of wildcat cartridges, and have never bought a box of storebought ammunition (only shotshells and 22 lr's). I have not only made my own cast bullets, but have made jacketed bullets as well, and have made from scratch cartridge cases for developmental purposes. I have pursued the unknown, and sometimes have won...and sometimes have lost! When I bring up an "opinion" it is based on all the experience I have had, and the results of that experience, and I am sure that there are some here who have no clue as to what I am talking about, or may dismiss what I am saying as falacy...but, "I" know what has transpired within the sphere of "my" experience. I do not offer up my opinion for ridicule or debate (which of course you have not done to me), but just to allow others an insight as to what "I" have done, and what "they" may possibly consider. Each "poster" on this forum is doing just about the same thing, and they do not deserve to be demeaned in any way, but, as I said before, we need to leave the final decision up to the reader as to whether what has been suggested is correct for his application. Also, anyone getting in to reloading really needs to start at the bottom (I did as well), follow the guidance of thier reloading manuals (I still have my original Lyman and Ackley manuals, and some newer versions), and maintain an understanding that by not doing so at that level of experience, could lead to a damaged gun or worse. I have seen many blow ups in my day, and most resulted in physical harm to the shooter and bystanders, and in a few cases death! We surely dont want anything to happen to anybody, but, we cannot control what everybody does all the time! So, the new reloader needs to take responsibility for "his own actions" and pursue this hobby in a safe and sensible manner. Any person that is new to reloading that jumps into high pressure top end loads, or non-standard modifications to loading data guidlines is a problem waiting to happen, and is a lost cause to begin with....some folks "just dont get it" and the only way they will understand is to suffer the consequences of their actions. Unfortunately, that is just human nature in some cases!!! In closing, "opinion" should flow freely on any forum.... and, "let the reader beware" should be the rule of the day!....By the way, as fortunate as I have been to pursue this sport/hobby in my lifetime, and the wealth of experience that has been garnered by that pursuit, it still amazes me that a relative newbie can still teach this old dog new tricks (I never will know everything there is to know), and that is the beauty of this whole experience. I hope you have a wonderful Thanksgiving! Take care!

A different perspective

flat top,
Happy Thanksgiving to you as well.

As far as opinion goes, to me, this is not a topic that should be based on opinion. It is first and foremost a safety issue.

What kind of bullet at what velocity or with what powder or any myriad of things can be based on opinion and have no affect whatsoever on someone's safety. Deep seating bullets and the corresponding rise in pressure from doing so is based in science and is a fact regardless of your or my opinion on the matter, period.

Let me give you this analogy:

My neighbor's house is on fire. I sit in my driveway wondering how it started. Then I remember, I showed their little boy how to "flick his Bic" so to speak. At what point do I assume SOME responsibility in starting the fire? Sure, the kid did it but he wouldn't have even thought of it on his own had I not espoused it. To my way of thinking, I would share just as much responsibility as the youngun' for actually starting it.
To me, and it may not be that way with others, I am going to do all I can to keep that from happening. Same here on this issue.

I am going to openly warn folks that following some advice, that advice that flies in the face of safety, of how dangerous it appears.

I have no agenda about having to be right, I just don't want to have the "blood of innocents" on my hands.

Shovel,
One friend of mine has a favorite saying: "When you find yourself beating a dead horse, by all means, dismount!"

I suppose it is time to do just that! (That is as long as the horse is dead! )

Tell; Just about every post in Reloading is based on "opinion from experience". I think it would be wise to take the most up to date reloading manual that is in publication...make it a "sticky", and when a question is asked, just refer the asking party to the sticky....problem solved!

"Safety" is a big part of what I do for my primary income. I work for a nationally recognized racing organization and safety is my primary responsibility. Even though the racing organization and myself do everything within our power to insure racer safety, there is no guarantee that every racer will adhere to all the safety standards and rules all of the time, and of course, we cannot ride with every racer during the race to insure that he does. In this racing organizations rules there is a "legal" clause that in part says, that even though the racing organization does all within its power to insure safety (we actually go well beyond that requirement), that "ultimately" it is the racers responsibility to comply with the safety rules and regulations that govern the sport.....personal responsibility "must" play a role in everything we do...be it racing or shooting....or, in our every day lives.

By any chance, do you work in the "safety" field...like for OSHA or something? Like me, you seem to be consumed with "safety".

No, I'm not in OSHA or anything but am intimately involved with industrial machinery. That's a place where ANSI and of course, OSHA standards are constantly applied. Mostly in metal working, punch presses, roll forming and other hazardous machinery. The kind that can take an arm off in one swipe type of stuff.

To use that field for a similar analogy, I would no sooner remove all of the warning labels and expect someone to have or attain the knowledge of safe practices on their own. Neither would it be, as I feel this issue brings to the forefront, post a safety label on a steel shear that says: "Go ahead, stick hand here and press the foot pedal, if you are fast, you can pull it out before you lose it!"

Again, while it is ultimately our own personal responsibility concerning our safety, you would have to agree with this too, we have to have the information to make the correct conclusion.

There are "Cowboys" in every field, without a doubt. Hopefully, they haven't been informed to THINK that riding backwards, at a full gallop, with no saddle, on an un-broke horse in a paddock filled with rocks is a SAFE endeavor.

Kapeesh? I hope so, now my legs are getting tired of spurring this animal!

Tell Sackett.....A Real Gentleman

"Again, while it is ultimately our own personal responsibility concerning our safety, you would have to agree with this too, we have to have the information to make the correct conclusion."

On this topic, COL, the information was given in its entirety in the link in the first post.

This horse is dead.

Tell Sackett said:

To represent things in the proper light of the topic, I think the discussion went more like "Don't do it arbitrarily without regard to powder charge."

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IMHO, at this point...you had made your point and made it well. The link was there for all to read. Anyone who can...would.
To proceed as you did was surprising, unnecessary and offerred nothing of value to the readers.
Sonny

sonny said:

IMHO, at this point...you had made your point and made it well. The link was there for all to read. Anyone who can...would.
To proceed as you did was surprising, unnecessary and offerred nothing of value to the readers.
Sonny

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Sonny,
This is true and I would appreciate it if you would accept my apology for continuing the discussion.

I will explain my intent simply as this; there is more than one reliable source that would refute the OP's information.

Once again, sorry for the intense informational deluge!

Calaveras Slim said:

Tell Sackett.....A Real Gentleman

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Calaveras Slim ...... a great judge of character! (Just Kidding! )

A humble thanks to you sir!