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View Full Version : OK, basic question time again....



Blammer
12-17-2007, 10:33 PM
I am loading for a Rem 700 30-06.

I am trying a 311284.

My first attempt at this boolit was to size it to .311 and seat it.

I found that unless I seated it to this lenght. See pic (OAL of 3.210) it would engrave in the throat hard, made it darn near impossible to close the bolt.

I engraved one boolit and then took it out and measured it and it measured .310 where engraved and .311 where not (since sized to .311)

The pic also shows the max lenght I can seat the boolit before the top band engages the throat.

The nose is .302 and does not engrave.

I was hoping to seat this out a little farther to have the GC in the neck of the case.

I am trying for an accurate load and from what I gather I need to have the GC in the neck, and size the boolit to....what size?

BTW my barrel slugs at .308.

Given what you know and what you do, what would you recommend I do? Or what would you do with these dimensions?

http://i54.photobucket.com/albums/g81/blammer8mm/Cast%20boolits/DSCN6281crop.jpg

garandsrus
12-17-2007, 11:21 PM
Blammer,

I would seat the boolit to the crimp groove and give it a try... I have never shot a 311284.

John

405
12-17-2007, 11:50 PM
Actually I've read here kind of a concensus that the GC should be in the neck. While there are many, many folks here with more experience than I in dealing with this issue, I'd prefer the whole bullet shank to be within the neck. Even with regular "jword" bullets- I hate it when the base is sticking into the case body :(. Never found any advantage to it and in some cases can cause irregular internal pressure curves with certain powder/bullet/chamber combinations :(. Anywho, I'd try to get the base of GC at least to the junction of the shoulder/neck. Next would be to try say a .308 or .309 bullet to see how much force is required. Also, the BHN number in combination with the bullet diameter could affect how much force is required to engrave. Forcing the bolt down with much effort seems too much. Another thing if I read your post and picture correctly is that the throat length on your rifle appears to be about 1/2 the length/width of top bearing band. Actually that seems pretty good to me. Some rifles have too long a throat- then a bigger problem usually comes up- can't get the bullet remotely close to the lands! If going to the .308 or .309 bullet doesn't work then a shorter shanked bullet would certainly do it but that is not what you are trying for with this load. One final thing to try would be to go to a lower BHN maybe 10-12. But that will require a lower velocity but that may be OK if the primary goal is accuracy.
Keep us posted if you crack this one. Good luck!

Buckshot
12-18-2007, 12:29 AM
...............If your throat is .310", size it .310"and seat it out until the nose engraves in the leade if this is possible.

http://www.fototime.com/A9E961604F79E6B/standard.jpg

This is the 311284 as I use it in a bolt action (small ring Mauser) in 7.62x39. The throat is .310" and I size to .3096" in a polished .309" die. As you can see the nose is engraved quite well:-)

BTW, as a rule I generally Tumble Lube bore riders before lube-sizing. The lube on the nose certainly helps it engrave easily, and I also think it doesn't hurt to have some lube for the nose to run on.

...............Buckshot

405
12-18-2007, 01:02 AM
Could be some mis-communications about what is called what. Without getting a direct reading from a chamber casting don't know how to tell exact measurements for the throat. It's either getting fuzzy brain late or I was reading Blammer calling the "throat" a couple different things in the original post question. Engraving usually means where the top band of the bullet (or full bullet diameter) begins entering the lands and engraves. The throat is an entirely different critter. The bullet shouldn't engrave the throat but should be just under throat diameter as Buckshot describes. Blammer, you might also get a chamber length reading on your rifle. A really hard bolt closing could also mean the case is too long or chamber too short and the mouth is trying to swage into the throat.... not a good thing! By getting that measurement you can eliminate one variable and trim your cases to .010" or so under and proceed with confidence!

Sailman
12-18-2007, 05:29 AM
Blammer

I have expairmented with seating a cast bullet with the base of the bullet below the case neck and into the shoulder area and with the bullet base not into the shoulder area. There was NO difference in the group size between the two different bullet seating settings. Based upon these findings, I do the following to establish the seating depth of the bullet into the case:
1 Drill out the primer pocket so there is only one hole. This tells you that this case is a
bullet seating gauge.
2 Full length size the case
3 Seat the bullet further out than you expect the bullet to be seated.
4 Take a black marker pen ( felt tip ) and blacken the entire bullet
5 Put the cartridge into the chamber and start to close the bolt.
6 If you feel the bullet starting to engage the rifleing, pull the cartridge out of the
chamber. You will see bright scrape marks on the bullet.
7 Seat the bullet a little deeper and blacken the bullet again.
8 Repeat setps 5, 6 and 7 untill you can close the bold and there will be NO scrape marks
on the bullet.

At this point you have established how far into the case the bullet should be seated. Remember, it makes NO difference if the bottom of the bullet is below the neck of the case.

Now you want to establish what diameter the bullet should be sized. Let The Rifle Tell You What Size It Likes. You do this by sizing 10 bullets .3o8, 10 bullets .309, and 10 bullets .310,
also .311 if you have all the sezing dies. Go to the range and shoot 10 rounds each of .308, .309, .310, and .311 diameter bullets with the universal load of 16 gr of 2400 for 30-06. See Cast Bullet Loads For Military Rifles in the CB Loads for Military Rifles.

Now you have let the rifle tell YOU what size bullet it likes.

Next load 20 rounds with the size of the bullet the rifle likes and the seating depth you have established, and shoot a 20 round group. Remember, in basic statistics, the larger the sample size the better you forcast will be. 5 shot groups are nice but a 20 shot group will tell you a lot more. However, if you are not weighing the bullets, you can expect from a 20 shot gourp one flyer, and two wide shots. This is not always the case but it can happen.

Now, you have established the following:
1 The seating depth of the bullet.
2 The size of the bullet the rifle likes
3 A good starting point with a universal load for your 30-06 rifle.

Hope this is of help for you.

Sailman

Char-Gar
12-18-2007, 06:38 AM
Blammer .... Buckshot be right!!!

mroliver77
12-18-2007, 08:37 AM
Blammer,
As Buckshot has said you need to size bullet to the throat size. Read up on this. I have slugs of all my rifle throats and size accordingly. It is not hard to do. From what you state it sounds as if your throat might be .310. It would be a good place to start. If you are engaging the rifling at this OAL there is nothing you can do but load this length. "or cut a deeper throat" There are a lot of opinions on bullet rivetting etc and I try not to use bullets that stick into the case if it can be avoided. I wouldn't sweat it though and just load and shoot some of them and see what you come up with. But as I said, read all you can about chambers and throats.

Blammer
12-18-2007, 12:25 PM
GREAT INFO guys! For some reason I got two posts of the same info going! I'll just post here now.

Here is some measuring I did!

OK, did some measuring.

Barrel, .3015 x .308
.308 being the groove and .3015 the land
The Nose on my boolits meaures .302 :)

.300 freebore at a dia of .310

Rifling starts at 2.790.
Measured from a bullets seated in a case then chambered and removed.

OK, thanks for all the tips and help! I got a good place to start now!
I believe a good combo of the above will definitely give a great start!

All I presently have is a .309 and a .311 sizer, looks like i"ll need a .310 now!
Hope Lee makes one that size!
My alloy is WW's only and just AC'd.

45 2.1
12-18-2007, 01:00 PM
All I presently have is a .309 and a .311 sizer, looks like i"ll need a .310 now! Hope Lee makes one that size!

That is a custom size from Lee.

What you need to do is: Take you 0.311" boolits and run them up in the taper portion of the 0.309" die enough to taper the leading edge of the front band so that it will chamber and lightly engrave when the boolits GC is at the base of the neck. Tap the boolit back out the bottom of the sizer with a wood dowel that is fitted to the boolit nose.

HORNET
12-18-2007, 01:40 PM
Blammer,
.3015 bore dia. and .302 boolit nose ? Should be good, probably getting enough to support the nose but not enough interference to deform it enough to leave visible marks. I'd size some .311 and some at .309 and try them. Let the gun decide which it likes :-D. I'd bet on the .309, though. Some body on this board (CRS) posted a while ago that they recovered some boolits that had been sized over throat diameter and found little chunks broken out of the front bands. That can't be good :(.

Blammer
12-18-2007, 08:54 PM
OK, I shot the three boolits that I loaded and that are in the pic.

Stats on that were

Rem 700 Gold 30-06
311284 sized with LLA to .311 in Lee, Hornady GC
Win case trim 2.490
WLR primer
13gr Unique
OAL 3.210 (which is what is shown in the above pic for length)

at 25 yards put 3 shots into .6 of an inch measuring the outside edge of all the holes on the paper.:mrgreen:

It shoots an inch lower than my 155gr 311466 with the same powder charge and same everything. Not surprising for a boolit that wts 70gr more.

Just for grins I'll load some more and check velocity with my chrono, and load some with .309 sized boolits and the same setup and see how they do for accuracy.

I'll try to shoot these tomorrow, providing the weather cooperates.

Buckshot
12-19-2007, 03:31 AM
...............Blammer, that's a good start. But at 25 yards those boolits from your '-06 don't even know they're alive and have been set free yet :-)

...............Buckshot

Blammer
12-19-2007, 10:22 AM
true, but it's all I got at the moment out the back door.

I have to go to the range to get any more distance.

But at least this gives a fairly decent starting place.

If it was a 2" group, back to the drawing board!

txbirdman
12-19-2007, 11:52 AM
This thread is very interesting to me in that I'm going through the same process with my Savage 110 in 30/06 with the 311291. Last night I tried seating this bullet sized at .311; .310; .309; and .308. I was "long seating" the bullet and letting the rifle determine maximum OAL. I don't have all my measurements with me just now but it seemed that the .308 had an OAL of 3.060 while all the others were seated much deeper. Also it seemed that on everthing other than the .308 sized bullet the front drive band was in contact with the throat and was in fact engraving the bullet not allowing the nose to contact the lands. I'm going to try the .308's on the range first and then work my way up the ladder. Seems I need to buy a little Cerrosafe.