Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Hunting > Long Range Hunting & Shooting

Long Range Hunting & Shooting Nightforce Optics


Reply

My new .300 RUM

 
LinkBack Thread Tools Display Modes
  #8  
Old 09-29-2003, 03:14 AM
Platinum Member
 
Join Date: Jun 2001
Location: Palmer, Alaska
Posts: 2,539
Re: My new .300 RUM

25-06,

I'm shooting 90gr Retumbo under the 200gr Accubond and all I can say is that it shoots great in this sporter I have.

Are you sure you didn't get the dent from too much lube when sizing the case? Dented or collapsed? Outside diameter of the neck before seating should be no more than .003" - .004" less than it is after the bullet is seated, for a press fit of that much. .002" is what I use, but My die uses neck bushings, so I do have better control of it than you may. Excessive press fit, lack of a mild champfer is the only thing I can think of that would collaps and round shoulders tho.

My loads OAL is 3.660", as long as the mag box will allow.

After you fire the cases once, you can partial full length resize (P-FLR), but you need a neck sizing die to just size the neck and leave the body alone.

To P-FLR cases, run the FL die down to the shell holder and back it off a turn or so, enough that when you size a case, the case will not chamber in the rifle. The reason it won't chamber in the rifle now is that the body has been squeezed in and the shoulder has actually moved forward as the brass worked forward. The die is too far up to make contact with the shoulder when it's sized, at this point this is what you want. Now that the case is too long to the shoulder at the datum line, adjust the die down 1/16th turn at a time until the case just chambers in the rifle with not too much effort on the bolt. Remember to lube the case each time you run it back in with the die a little lower or [img]images/icons/shocked.gif[/img] . What you want, and are trying to achieve, is a case that is forced against the shoulder and the boltface with zero headspace and is thus centered up in the bore perfectly, just allowing you to close the bolt.

You can monitor the headspace length with a Stoney Point tool or just use an empty 44 Mag case slipped over the shoulder to measure it. The length to the shoulder on your once fired cases will probably be a little shorter than the number your looking for (a thou or two).

What you're trying to do is to keep the cartridge from laying on the botttom of the chamber by forcing it up tight against the shoulder which will center it up, this way there is clearance between the neck and the chamber all the way around, and the bullet is thus centered to enter the bore perfectly when fired.

Properly set up this way, headspace will always be the same from one loading to the next, not getting tight after a couple as it will with only neck sizing, thus requiring a run through the FL die, which will possibly change the way it shoots when you do.

If case neck runout becomes a problem, and it easily can if you neck size, P-FLR or FL sizing will eliminate it or almost completely do so, neck sizing will not, and can multiply it as well.

Good luck this season. [img]images/icons/smile.gif[/img]

[ 09-29-2003: Message edited by: Brent ]
__________________
Brent Moffitt
Reply With Quote
  #9  
Old 09-29-2003, 02:28 PM
Platinum Member
 
Join Date: Jun 2003
Location: Hermiston, Oregon
Posts: 2,005
Re: My new .300 RUM

Brent

It was not caused by to much lube. The whole top of shoulder right below the neck was collapsed and totally transformed. It looked like a Weatherby design of the double radius.

My rounds are loaded to 3.6" which is shorter than yours of 3.660" and about 6 of my shells are pretty hard to get the bolt to shut, although when I resized the cases, before putting powder and bullets, there was no problem getting the bolt to close. The bullets aren't anywhere close to the lands.

I tried the Partial Full Length Resizing on a couple caes and I think I'll probly stick with that. It sounds better than neck sizing, and I wouldn't have to buy another die.

Would the set up I have be good to hit a 27" tv screen at 1000 yards? There is a local competition every year and this year I want to enter. My scope is a Leupold VX2, 6-18 Target with Leupold bases/rings. I am more than likely going to use the 200g SMK.
Reply With Quote
  #10  
Old 10-01-2003, 02:56 PM
Bronze Member
 
Join Date: Jul 2003
Location: Bountiful, Utah
Posts: 71
Re: My new .300 RUM

Since I just got a 700 LSS in .338 RUM, and I've been going through the process breaking of it in and working up loads, I can share a few observations:

1. Your cases might be getting squashed because there is no chamfer in the factory cases. Take your little tool and chamfer the inside of the mouth just a tad. My factory cases were nice, but still had a few questions when loading them up for the first time. Once I started chamfering the mouths, which is normally not a big concern, the force to seat the bullet dropped in half. It was an unusual occurance.

2. My factory barrel was ROUGH! I had 160 rounds down the barrel and it was still fouling really bad and the accuracy wasn't all that great. That was after pillar bedding the laminated stock, floating the barrel, and adjusting the trigger to 3 pounds, AND installing a Vais brake and re-crowning the muzzle. My 'smith scoped the bore and the last half of the barrel was STILL very rough. I talked to a guy that had a .300 RUM that had the same problems. Very rough bore and poor accuracy. He had his barrel lapped and it solved the problem. I ended up fire lapping my barrel using Tubbs Final Finish. Check it out, it works well. Now it's shooting well.

3. The factory crown was BAD! The factory tool chattered on the crown. Not a pretty sight. Check it over closely.

I'm now getting a 9/16" pattern, which is a ragged hole with this using 250 grain GameKings and 83.2 grains of IMR4831 scooting along at 2859 fps. I got up to 3004 fps, but the accuracy wasn't there.

The loading charts are very conservative. I ran out of space using WC872. 104 grains is a compressed load, and is about the same speed as H870 or H1000. I've put up to 93 grains of WC852 (mil-surp 4831) and got 3077 fps. So far no visible pressure signs. Your .300 may like slower powders more, but don't be afraid to give 4831 a try.

4. Plan on bringing a towel soaked in ice water to the range to cool the barrel. I can get off about 20 rounds an hour and keep the barrel cool enough to hold with my hand. Shoot 5 shots, wrap in cold towel, clean barrel if needed. When cooled, shoot 5 shots and cool it down again.

5. Recoil will be about double that of a 7 mag. Plan on it. Take the appropriate precautions. A 10 pound bag of lead shot I've heard does wonders. My brake works well for me.

Have fun and burn LOTS of powder!

Mark in Utah
Reply With Quote
  #11  
Old 10-01-2003, 04:29 PM
Silver Member
 
Join Date: Apr 2003
Location: Newburgh NY
Posts: 235
Re: My new .300 RUM

25-06 you are probably over crimping the case!!! The RCBS seater dies are meant to have a crimp feature which if you mean to do it has to be set up properly. If you do not want to crimp all you have to do is back the die out of the press slightly and adjust the seater stem down with the screw. If you are trying to crimp with this type die your trim heights and chamfers all have to be perfect!!! If you must crimp I would suggest seating your rounds with the die and getting a Lee Factory crimp die for crimping!!! Personally I do not crimp my ultra rounds.
Good luck!!!
Reply With Quote
  #12  
Old 10-01-2003, 04:33 PM
Silver Member
 
Join Date: Apr 2003
Location: Newburgh NY
Posts: 235
Re: My new .300 RUM

25-06 PS I use the same load of reloder 25 at 95 grains and 178gr Amax. I get 3300 out of the 26" barrel. I wouldn't even try to get 3500 as you suggested before because it will be way high on pressure!!!
Reply With Quote
  #13  
Old 10-02-2003, 01:04 PM
Platinum Member
 
Join Date: Jun 2003
Location: Hermiston, Oregon
Posts: 2,005
Re: My new .300 RUM

I bought a box of the factory 180g Nosler Partitions to shoot for breaking in the barrel and to get me started with 20 pieces of brass. I shot and cleaned after every shot for 10 shots, then shot 3 shots and cleaned till I was out of shells. 3 shot groups were a little over an inch with a flyer because of cleaning. On all my groups, the 1st shot was always a flyer but the 2nd and 3rd were 1/2" groups. They chronied an average of 3245fps 15 feet from the muzzle with no more than 30fps being the maximum deviation in velocity, and on a 80 degree day. I then shot 3 shots at 300 yards with the 180g Nosler partitions and it measured just over 2 inches. Next I tried my reloads of H-1000 and 200g SMK's. I loaded up 3 different loads or 9 shells altogether. 91g, 92.5g, and 94g of H-1000 seated to 3.6" They all gave me 1/2" 2 shot groups with the 1st shot on all of them being a flyer due to cleaning the barrel I suppose. I chronied the 94g load right at 3200fps. Maximum deviation was 25fps. I will try them next at 300 yards then sight in dead on at 100 and get my ballistic charts ready at least out to 600 yards on Friday and shoot a couple at milk jugs at 500 and 600 yards to test out how close they are and make any final adjustments. My deer season starts Saturday so I will be hopefully done just in time. I'll keep all posted on how everything goes.

PS. I got the small problems fixed. Thanks for all the helpfull advice.
Reply With Quote
  #14  
Old 10-02-2003, 02:42 PM
Bronze Member
 
Join Date: Jun 2003
Location: Eastern US
Posts: 61
Re: My new .300 RUM

Remingtonman_25_06

Good to see you get that rifle! I was wondering what happened to you. Last we heard, you were thinking of getting a 300 Win Mag heavy barrel but opted for a Remington 243 ADL synthetic, I think. Anyhow, I'm glad you were able to get a big game gun for Long Range. I have been testing my 7 RUM and found, so far, that it likes H-1000 too. As for neck sizing, I wouldn't worry about it too much. The latest Sierra Manual said that "contrary to popular belief most bench rest shooters don't strictly neck size but full length size" I have always FL resized and haven't had any problems. However, I am new to shooting 700 + yards too with rifles (well hunting rifles anyway, Uncle Sam let me fire all sorts of **** much further than 700 yards!) So, unless I can't get the accuracy I want from FL sizing, I'm not going to worry about buying the dies. Being new to this LR stuff, there's a learning curve which we're going to have to go through. Anyhow, keep us posted. Those 700 BDL laminates really look sharp!

Good luck!
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Current Poll
Do you archery hunt for elk?
YES - 32.14%
63 Votes
NO - 52.04%
102 Votes
Not yet, but I plan to. - 15.82%
31 Votes
Total Votes: 196
You may not vote on this poll.

All times are GMT -5. The time now is 11:29 AM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC