COL situation

[OLDVET]

I reload .223 and .308 cases. I use a RCBS Rock Chucker Supreme single stage press. I resize my .223 cases with a RCBS small base die and use a Lee bullet seating die to seat the bullets. I use the Lee three die set for my .308 cases. I get varying C.O.L. lengths with both dies. I want an overall length of 2.25" for the .223 and 2.75" for the .308. When I set the seating die and load my first shell, I can get the required length. The next bullets may be as much as .08" either longer or shorter than the first shell. This requires a constant adjustment of the bullet seating die. I position the bullet the same way on each case and operate the ram lever to it's full extents, but the problem persists. I thought it might be a difference in case manufacturer, but seating bullets in the same brand of case still causes the same problem. This is more of a nuisance than a problem. I assume this is not a normal function of reloading bottle neck cartridges. Anyone else have experience with this?
I looked into Competition Dies. Theses dies have a micrometer on top. Would this knob be for adjusting the final bullet depth? My Lee bullet seating dies have an adjustable knob which allows for this final adjustment with out having to loosen nuts like other die sets such as the RCBS dies. I have been loading these two bullets for about a year, so my experience level is limited. Any experienced information would be appreciated.

 

[ROGER4314]

The OAL dimension is a maximum. As long as the bullet doesn't contact the rifling as it is chambered, there is little problem. Granted, accuracy depends on consistency but that dimension is of lesser consequence than other factors. Are you sorting your cases? There is a lot of variation between case lots and/or brands.

Look for a collapsed shoulder on your cases. The .223 is bad about that. A tight bullet fit in the neck will cause a slight bulge as the case shoulder collapses. Carried to an extreme, the round won't chamber. That can easily make the variance you are seeing. Make sure there is a slight chamfer on the inside lip of the cartridge neck so the bullet won't scrape as it is seated.

Flash

 

[OLDVET]

I have tried sorting the brass by manufacturer, but the problem still occurs. The problem happens with new brass as well as fired brass. I do chamfer the inside of the case neck as well as the outside. I also hand seat the primers to make sure they are fully seated below the case bottom. I am just amazed that I can repeat each step of the reloading process exactly the same way and have different overall bullet lengths. When I set up my seating die, I raise the ram with a case in the shell holder. I then screw the seating die down until it contacts the shell case and then back it out about 1/8 turn. This allows the seating die to seat the bullet without contacting the case. This eliminates the chance of crushing the case neck.
Thanks for the feedback.

 

[GJW1911]

I have a similar issue to yours, and I found that normally the change in OAL is due to the bullet itself have varying over all lengths. When I buy new bullets I measure and sort them buy lengths. Separating the bullets into bags with bullet lengths varying no more that .01" in length.
Then when developing my loads I record the OAL of the bullet used and compensate when using new bullets and the bullet length changes.

 

[TexMex247]

GJW is right. It is the bullet. When I first started loading for the 223 i was using sierra bullets. Their oals varied almost as much as .025". It seems crazy but in spite of it, the sierra bullets still outshoot most of their counterparts. Lee dies also tend to "bottom out" adjustment wise before you can reach your preffered depth, so you might come across that problem next. Good luck with it and don't sweat a few thousandths of an inch. Unless they are bolt guns, the small differences won't matter.

 

[codygjohnson]

I vote bullet. Use a comparator if you have one. You will probably find that the distance from the base to the ogive is the same on all of your bullets, its the meplats that vary.

When I started loading the .338 Lapua, the Sierra 300 SMK was the most accurate bullet out of my rifle but the meplats were all over the map. I usually only measure cartridge legth with a comparator anyway, but you would have OALs that would drive you nuts. I had issues getting the rounds as long as I wanted them without having a few that would bind in the mag. I bought a meplat trimmer and now trim them all to the same length. Problem solved.

 

[medalguy]

The OAL difference can also be the ogive of the bullet. If you closely examine a batch of bullets you will find a little variance in the curvature of the bullet where the seater plug contacts the bullet. I was experiencing the same problem in spades when reloading some GI pulled tracer bullets but I found a way around this.

I load in a Dillon progressive but you can adapt my fix to a single stage press. I load and seat the bullets normally in the third station of the Dillon press but leave the bullet about .025 short of full seating depth. I place another seating die in station 4 but remove the seater plug and replace it with a piece of 1/4-28 threaded rod with the end ground flat. I can adjust the rod to finish seating the bullet to the exact depth I want without having to be concerned with the ogive of the bullet or bullet diameter where the seater plug would otherwise contact the bullet. Using this method I can seat every bullet to precisely the same depth with absolutely no variance in depth. If desired I crimp with a Lee FCD die in the 5th station.

 

[AusTex]

I didn't read the posts above so sry if this is been covered already but get yourself the HRNDY comparator gauges as it measures from the most consistent part of the projectiles the ogive.Hornady Lock-N-Load Bullet Comparator Basic Set with 6 Inserts - MidwayUSA. Just look at the tips of the bullets even high grade stuff each tip is different especially sierra HPBT. So when you put your calipers from the tip of the bullet to the rim because the tip of one bullet is longer than the next you are going to get variations in measurement. By measuring from the tip you measure your first bullet and you THINK that you have the COL of 2.25 however you just have COL of 2.25 of that bullet from measurement from base to tip.

Even more important really is to get the HRNDY OAL case Gauge. This is a tool that lets you measure your MAXIMUM OAL length of your chamber in YOUR gun. When you chamber a round the bullet can do about 2 things really it can either be Jammed into your LANDS(this means pushed into the rifling) It can be short of the lands(this means the bullet jumps through open barrel till it hits the riffling or if you figure out the OAL you can just kiss the land. This is important because all guns are different one rifle might like a few thousandths off the lands another rifle might like the projectile jammed into the lands. So you have to test for yourself and see what gets you the best groups(everything else being equal all cases trimmed equal, powder equal, same primer, blah blah blah)

.308 is very forgiving on necks I do not neck turn my .308 brass. The LEE collet dies does a great job at keeping that sucker straight. Read up on neck turning just to know but the short answer is if the neck has inconsistent thicknesses one part of the case might apply more pressure onto the projectile than others, thus causing the bullets to be pulled to one side and make the bullet wobble or be LESS stable. Again this is match grade important only really. The collet die does what is also known as NECK SIZING- compared to Full length sizing. Now you cannot Neck size in SEMI auto weapons(You can but you will get failures and it will wear out your extractor and other parts before the brass has gone bad anyway loosing the benefit of neck sizing) also you can only neck size brass to be shot in the SAME gun. Why does this help? it helps b/c when the round goes BOOM pressure pushed on the brass outwards and forms it to the inside of your chamber when you FULL length size this CUSTOM FIT so to speak is gone. Also when you just neck size your brass will last longer.

So I would get the setup from MIDWAY USA for the hornady tools I mentioned above. Only get it for these guns if they are BOLT guns. My opinion is that Semi auto guns it is not worth the money because most likely your CHAMBER OAL is going to be longer than the length your magazine allows you to load anyway. That being said load the .223 to magazine length unless you are shooting really light small projectiles or a bolt gun.

Are you shooting semi on both, semi and bolt, both bolt?

BRASS prep IMO is more important (primer pocket uniform and clean, flash hole Deburr, Trimmed to length, chamfered) Then I would say consistent powder and then I would say knowing the maximum OAL of Both your firearms then testing case OAL for performance in those firearms.

Again I made some assumptions in my post I did so b/c of your question please correct me. I am using CAPS LOCK on some words just to point out their relevance not to be insulting. I hope this helps.

Jeremy M.

 

[OLDVET]

I will look into the bullet lengths. I weigh each bullet and have found that Sierra bullets are dead on as far as weight goes.
I reload for my ARs and my Springfield M1A1 rifle. Both are semi-automatic. The Sierra bullets (52 gr. Matchking HPBT for the ARs and the 150 gr. Matchking HPBT of the M1A) are very accurate in both rifles. The local rifle range has a maximum distance of 100 yards, so I base my accuracy results on that distance.
I am a recreational shooter on the weekends. I no longer hunt. My evening hobby is reloading for the next weekend's trip to the range. I have reloaded for a few years with only a few problems. I use an RCBS small base resizing die for my .223. The first couple of reloading sessions yielded some problems. I assumed that once you set the die and tightened the set screw on the locking nut, you didn't have to reset the die the next time you reloaded. This error in judgment resulted in about 100 reloads that didn't have the proper shoulder length.They were about three thousands too short. This resulted in a few case separations. I now reset all of my dies prior to beginning any reloading step.
I wanted to see if anyone else was experiencing similar problems when they reload. I appreciate the information you guys have provided.

 

[AusTex]

I have used both of those bullets I would say to look into the 155grn palma by sierra. It has a b.c. of 504 and is the same length as the 175hpbt. It is about the only round I use in my 20" 1:12 twist bolt gun past 500 yards. My short barrel and slow twist make it hard for me to shoot the heavier bullets too far.

Also look at these in .308 and .223 Lyman Case Length Headspace Gage 308 Winchester - MidwayUSA This little guy will basically help you setup your dies much faster. If the loaded round fits and slides in and out with no problem then it will fit in your chamber if it doesn't you need to go back to your sizing die. I load in batches of 100 and after the batch I take the tray and go through ever 9mm bullet I load drop it in the top and turn it over to let it fall out. This also adds another step to ensure proper primer seating and case inspection in general.
It basically just ensures proper headspacing.

 

[OLDVET]

I loaded some Sierra 135 gr. Matchking bullets in .308 this morning. I checked the overall length of some of the bullets and found they do have different lengths. Some as much as .01" of an inch. I find this interesting since Sierra bullets are so accurate in their weight. I use Dillion case gauges for the .223 as well as the .308. Heading out to the range later to try this new Sierra 135 gr. bullet in my M1A1.