Bullet seating depth check please.

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Muddydogs

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Ok I used the Hornady OAL gauge to find the OAL of my Remington 788 243 and would like some feed back to make sure I am doing this right. I used the bullet comparator to do the final measurements. The comp length I got measuring off the lands was 2.337 inches. To start I was going to back the bullet .040 off the lands so that would be 2.297 or lets call it 2.300. The OAL of the cartridge is 2.710 which is also the max OAL listed in my Speer manual. Dose this look right? My throat seams to be quite long. Is there a problem with how far the bullet is set above the crimp grove (last pic)?

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Did the dial get turned after your measurement? Normally they are a little more "square" to the caliper.

I also reload .243, but I've never had one seated out that far.

I believe it is OK, provided

1. There is at least one caliber (.243) of bullet in the neck for tension (but this is a guideline...some cartridges have short necks that don't permit this no matter where you seat the bullet)
2. It fits in the magazine.
 
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When seating bullets for an auto loading action, neck tension becomes a bit more critical than for a bolt action or single shot. I would focus on seating to some where around the published OAL to avoid the risk of a bullet jumping out of the neck during cycling.

I'm not familar with the Rem. 788, but isn't it an auto loader? If it isn't, then ignor my post and go ahead and seat as close to the lands as you want. Some BR guys will seat right into the lands. With some cartridges like the 300 WM, the bullets will barely have any neck tension because of so little contact with the neck. Not a problem for someone who is familar with this, and probably not hunting with them, for obvious reasons.
 
Muddydogs,

Since the Remington Model 788 is a boltgun, assuming you have at least one caliber (.243") of your bullet in the case neck, you are fine.

Don
 
Yes the 788 is a bolt gun.

The bullet is a Speer Grand Slam at 100 grains. There is still a lot of bullet in the case. I will post a pic tonight with a loose bullet.

I have plenty of neck tension, I can feel it when seating the bullet and can not push the bullet into the case with stiff pressure against the work bench.

The dial on the caliper is off center as it is zeroed for the bullet comparator. With the comparator on the caliber the caliber reads 1.0 something ?. The dial is turned to adjust or zero the caliber at 1.000. and then 1.000 needs to be subtracted from the final measurement. Sorry I am old school and don't have a digital job, pointed one out to the wife for x-mas as she needs something to get me but I am ok with old school. Don't get me started on kids today that can't tell time on a analog clock or have any idea what a quarter till or a quarter after is.
 
OK, 1.000 makes sense.

I also use an analog caliper, but I just cheat and subtract everything with a calculator to get final dimensions. The 1.000 = zero looks easier.

I used to own an adding machine, to go along with the slide rule, but they have both been retired to the junk yard or museum status.

I figure I've almost achieved "obsolete status" by using a Palm cell phone... :)
 
No but is is a good place to start! This is what the book says should be good. It will be a lot better than the length he has it. Some people needs to read there reloading books before they start loading! The book has a length for all bullets they also have an OAL that will suite most people if they are not target shooters.
 
AABEN said:
No but is is a good place to start! This is what the book says should be good. It will be a lot better than the length he has it. Some people needs to read there reloading books before they start loading! The book has a length for all bullets they also have an OAL that will suite most people if they are not target shooters.
Click to expand...

Actually my books states that the max OAL is 2.710 and that is what the bullet in the picture is set at. Notice the first picture I posted has all this information. I am using a Speer book, Speer bullets ect so I would think that there info should be good. So what is the problem with the length I have it at? Who needs to read what? Obviously the crimp grove is no where near max length.
 
So I loaded up a few test rounds with Reloader 22 starting at 43 grains and ending at 45 grains. Max charge listed is 46 grains. I run mag primers so I tend to run a grain under max. So we will see what kind of groups we get and go from there.
 
So i went to the range today and I still have all my fingers, toes,eyes and teeth. Shot reloads out of the 243, 223 and 40 but since this thread is about the 243 I will give you just the details of this rifle. Shot 3 5 shot groups starting at 43 grains of Reloader 22 and ending at 45 grains at 100 yards. My groups where over an inch with the 43 and 44 grain loads then shrunk to .79 inches with the 45 grain load. Not sure if I have signs of pressure as some case heads have a bolt plunger mark on them and some don't. Primers just look like fired primers, I can never tell what a flat primer is supposed to look like. Measured the head space of the fired cases and came up with an average head space of 1.628. Measured some full length sized cases and they have a head space of 1.625 so thats only .003 inches set back on the shoulder which I believe is good. Need to do some more checking on high pressure signs on the net and work the load a little bit more to see if I can reduce the group size just a bit more. My parents are getting me a chronograph for x mas so I will be able to do some velocity stuff after then. And no I am not a kid, just happens that my folks can not not buy me anything for x mas and if I want something better then zip ties, bungee balls and carpenter pencils I better tell them or thats what I will get. Every year I try and tell them that I don't need anything but they won't listen. At 43 I have what I want or go buy what I want just ask the wife.
 
...some case heads have a bolt plunger mark on them and some don't
Click to expand...

If by this you mean a little mark that looks like the ejector cut-out in the bolt, that can be a pressure sign.

What little I know about pressure signs is that none of them are reliable. However, if you have a number of them, the odds of high pressure being true go up. :)

I think another indicator is difficulty lifting the bolt.
 
Why is it only on 1/3 of the cases? Its just a small square mark thats shinny and slicker then the rest of the case head. Each powder group has 2 cases this way for a total of 6 out of 15. The primers on these 6 cases as well as all the cases seam to be good to go. From what I have found on the web my primers are a little flat from the fireing pin strike but the edges are still sharp and there is still a gap between the primer and pocket edge like a fresh primer would have. Bolt was never hard to close or open.

I will try backing the bullet a little more off the lands and see what happens.
 
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