1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

300 Weatherby Magnum

Discussion in 'Handloading and Reloading' started by whiskey3, Jan 24, 2010.

  1. whiskey3

    whiskey3 Member

    I am new to reloading and the board. With that said I have some noob questions.

    I have done some research on loading this caliber. I have seen alot of comments about case/head seperations and brass bulging above the belt. Evidently Larry Willis of Innovative makes a special collet die for this problem, is it needed?

    Next, Weatherby made rifles are "free bore" and I don't think the 700 is, should I back of recommended loads for the Weatherby?

    My current load plan is to start with 80 grains of RL 22 with a 165 grain nossler ballistic tip out of a Remingtion case with a federal 215 primer. I also plan to neck size only as much as possible and set the bullet .020" of the lands. Is this in the ball park?

    Any help / guidance will be greatly appreciated!!
  2. JimKirk

    JimKirk Well-Known Member

    False headspace, created by oversizing brass can be blamed for most Belt case head separations. Because brass does not meet at the datum point(the belt) and the datum point(the shoulder) at the same time, brass flows. Guess where it flows from, the area right in front of the belt. Proper sizing would eliminate most of those separations.

    Jimmy K
  3. Innovative

    Innovative Well-Known Member

    whiskey3 .......

    JimKirk is right. When your handloads have excessive chamber clearance at the shoulder, your cases stretch when fired. This thins your brass just above the web, and if your cases are going to separate - this is where it will happen. I designed the Digital Headspace Gauge to help shooters "measure" this clearance (at the shoulder). That allows you to set your die height accurately without guessing.

    Our Belted Magnum Collet Resizing Die allows you to drop your case in the top, and quickly see when your cases are slightly bulged. Then the collet allows you to resize your cases all the way to the belt. This ensures that your handloads will always chamber properly.

    - Innovative
  4. K-DUB

    K-DUB Active Member


    Pm sent.
  5. ants

    ants Well-Known Member

    Get your own experience first.

    Welcome to the Forum, whiskey3.

    I generally neck size the 300WbyMag, but full length resize occasionally whenever needed. I haven't had the separation problems you read about, those problems are not universal. I'm sure the innovative die is very cool, but it is fair to say that I've never needed one. Perhaps you should start loading with conventional equipment and build up your own experience. Later you can decide what special equipment you need.

    I don't know what you think, but 300WbyMag is not like .223 or .308. Most owners don't shoot 2 or 3 hundred in a range session. Your shoulder just can't take that. One only shoots a dozen rounds or less, maybe 20 at the very most. If you build up a stock of 100 or more brass cases, they may last your lifetime before the brass stretch phenomenon becomes a problem (or you toss the brass due to split necks).
  6. rg1

    rg1 Well-Known Member

    Remington .300 Weatherby brass is heavier than Weatherby brass and has less internal volume. At least all the Remington brass I've loaded is. If the data you are using uses Weatherby cases in their test you need to reduce "maximum" loads for your RP brass by at least one full grain up to one and one half grains. My .300 Weatherby with Weatherby brass and 87 grains of Norma MRP powder with 150 grain Hornady bullets gets the same velocity as Remington brass with 85.4 grains. Norma MRP is nearly identical to REL 22 and I've heard that it's the same?
    My .300 Weatherby dies made or sold by Weatherby back in the 80's when setting the sizing die to touch the shellholder pushes the shoulder back too much. IF you full length size and your die pushes the shoulder back every sizing, then you will only get 3-4 loading on a case before stretching will make the case dangerous to use. Buy a case gauge to set your sizing die to only push the shoulder back 1 or 2 thousandths on your belted magnum cases. Like I said my dies are from Weatherby and are standard dies.
    Weatherby with the freebore will handle more pressure than the Rem 700. Need to check your chamber in the 700 to compare it to the Weatherby. Bullet seating lengths to rifling will be different for both. I load Hornady 150-165-and 180's and Nosler Partition 200 bullets and seat them to Weatherby recommended overall length and accuracy is good. With the freebore in the Weatherby don't know if you can reach the lands without too little bullet inside the case mouth. 1st thought you had 2 rifles, one Weatherby and one Remington 700 but looks like you have a .300 Weatherby chambered Remington 700.
    Last edited: Jan 25, 2010
  7. Innovative

    Innovative Well-Known Member

    Reloading belted magnum calibers is a bit different from non-belted calibers. Factory ammo headspaces on the belt. However, handloads need to headspace on the shoulder. This prevents the shoulder from being blown forward every time it's fired.

    The very first firing of a belted case always stretches the case quite a lot, and this weakens the brass considerably. After that, it's important to minimize chamber clearance at the shoulder. That's how you can avoid headspace separation. This picture shows how your case is affected on the inside.


    Case wear (on the inside) begins long before you see any signs on the outside of the case.

    - Innovative
  8. JimKirk

    JimKirk Well-Known Member

    This effects ALL belt cases except for the straight wall ones like the 458 Winchester or those with so little shoulder that have to use the belt for headspace.
    Jimmy K
    Last edited: Jan 28, 2010
  9. GooseGestapo

    GooseGestapo Well-Known Member

    Early Weatherby rifles (the one's made in Germany) had 0.500" freebore, or in some cases I heard of, even longer freebores.

    Back in the late '70's or so, Weatherby standardized on the 0.375" freebore, and most rifles I've checked had such.

    I'm not sure about the chambers on the Remington. I suspect they are likely with the same chamber as the Weatherbys. The Norma ammo is loaded right up to the allowable pressures for the Weatherby mags. so, if fired in a Remington with a shorter chamber it would predictably cause problems. I'm sure Remington did their homework on these before releasing them.

    I've got a Savage M110 in .300RUM, and it too has a 0.375" freebore just like my .257WbyMag does. So, I suspect your Remington will likely have a similar chamber.

    Do start at the recommended START loads as no two rifle chambers/barrels are identical. Back off another 5% if using other than Norma/Weatherby brass.

    Don't feel you have to "Max-Out" your reloads. My favorite loads for my .300RUM are at or even below some of the the recommended "start" loads. One such is a load I picked out of the Lee #2 manual for IMR7828 and 165gr bullets. It's a .300WinMag class load that is superlative accurate and recoil is much moderated from the 100+gr loads of Retumbo. Guess which load I shoot more of ??

    Like other poster noted, only size your brass enough to allow free easy chambering. Avoid pushing the shoulder back upon resizing and you'll get good case life.

    I've found that the cases I've formed for my .257wby from Remington 7mmMag brass is approx. 5% less case capacity, and Max out at 2-4gr below what is book max for the Norma/Wby cases. Not as accurate as the "factory" brass either, even though I've neck turned them and matched for weight, ect..... I believe it's the extra 0.05" case neck length. O'l Roy knew what he was doing when he designed the cartridges afterall......
  10. Grumulkin

    Grumulkin Well-Known Member

    There are several points I would like to make:

    1. I have the "special die" and in loading for at least half a dozen belted magnums, I've never needed to use it.

    2. Much ado is made about neck sizing. Yes, it can improve brass life but sometimes at the risk of having some rounds not chambering easily and, unless you're using very good dies for a bench rest gun accuracy may actually be worse with neck sizing than with full length sizing.

    3. In working up a load, you should ALWAYS start toward the lower end of the recommend loads. If you do this and stop increasing the load when pressure signs appear, you will not have to worry about things like freebore or using a particular brand of brass.

    4. It's interesting that so much is made about belted rounds being head spaced on the shoulder. Really, it's OK to head space on the belt and in rounds like the 458 Lott, 375 H&H Magnum and others you have to.

    5. All cases whether straight walled, belted, etc. will stretch. How soon a head space separation will occur depends on many factors including how sloppy the chamber is, head space, load pressure, brass properties, etc. For high pressure loads like the 300 Weatherby, you should get used to checking for incipient head separation after the second reload. Run a wire with the tip bent to 90 degrees down the inside of the case to feel the groove that starts above the web before head separation occurs.
  11. Innovative

    Innovative Well-Known Member

    Grumulkin .....

    As you mentioned, it's a very good idea to examine the inside of belted cases. Read the Reloading Questions section on my website, and you'll see why (and how) the life of your brass can be extended. The Reloading Tech Tips and the Testimonials sections are pretty good too.

    This site is a great source of information! However, sometimes there's just too much information to discuss in a forum, and it's very easy to leave something important out of a typed conversation. Nobody wants to experience a headspace separation. It usually just creates a minor damaged case. However, pressured hot gas blasting back through your bolt is a real possibility. It's best to read "the whole story" instead of getting information in random bits from everyone on the Internet.

    - Innovative
  12. ants

    ants Well-Known Member

    Innovative, just out of curiosity. How many of those dies do you sell each year? Just curious, no big deal if you don't have the figures handy. :)

    There are probably a hundred thousand belted magnum reloaders around the world. Each probably has his own experience loading, and most probably don't even know you have a collet sizing die available. Most probably aren't even aware of a brass flow problem.
  13. Innovative

    Innovative Well-Known Member

    ants ........

    The high number of shooters you mentioned is why I patented our collet die (Pat # 6,412,385). At this point I've sold just over 3,000 of these dies, (and I've only had one of them returned). That's a pretty good record considering that I'm a one man company that hasen't paid for advertising, and I don't sell through distributors.

    I used to sell our collet dies through MidwayUSA, Cabella's, Lock Stock & Barrel, R.W. Hart & Son, and Midsouth. However, thanks to all of the lawyers out there . . . . distributors are required to purchase only from manufacturers that have a million dollars of liability insurance. I had that policy for 2 years, and the cost kept going up - up - up, so I dropped it.

    When I went to selling direct, the volume of sales stayed almost the same due to satisfied customers and word of mouth advertising. It also saved from paying the middle man. This has given me the chance to work directly with hundreds of shooters.

    Our Digital Headspace Gauge is NEW and it's only been seen in The Handloader magazine one time (October 2009, page 102). Advertising is unbelievably expensive, so you'll only see our products on my website. Even so, our new Digital Headspace Gauge has already sold almost 700 units so far. Believe me, there are a lot of awesome shooting products that will never be seen by most shooters. Thank a lawyers for that!

    If you visit the Annual Shot Show you'll see plenty of great products that will never even be manufactured.

    - Innovative
  14. whiskey3

    whiskey3 Member

    Thanks for all the info, I guess reading all the information about case seperations had me worried about loading this round. I think Ill just start on lower side and see what happens!!
  15. JimKirk

    JimKirk Well-Known Member

    I own a Remington 700 BDL 7MM magnum. The guy I bought it from was having his cases "almost" come apart, he was letting some knot head reload his cases for him. Time and time again, tried to tell him that he needed to adjust his dies correct and his problems would go away. Well he shows up at my shop one evening with his gun in hand and before he he got to the door, I told him that I would give $275 for his problem gun. He accepted it. Two days later he comes back with a set of Redding dies and hands them to me, saying that they went with the rifle. He also had a paper bag of may be 150 cases. I offered to pay him for the dies, but he would not take it. As soon as he left, I walked over to the trash can and threw the bag of brass away(before good scrap $$). I ordered a 100 new RP brass from somewhere and promptly adjusted the dies. Twenty years later and after many many shots, I still have all that brass except the three that I sliced open to look at.

    I not going to knock Larry's products because I've never used them. I could see the benefit of using the collet IF I swapped cases among different rifles or you had a chamber that was off enough to warrant using them, but I don't.

    Adjust your dies right and you won't have any problems!

    Jimmy K
  16. WV_Vizsla

    WV_Vizsla Well-Known Member

    Never a split case

    I did not find the 300 particularly had to load for. Should pull the trigger on my 1K this summer. But I do more inspections and check for case stretch. I do have my die a smidgen off of bottom to not push the shoulder back too far every time. Also.. speed faster than 3000 or 3300 comes at a cost of brass and shoulder cartilage (yours). I mark every case with Sharpie in the numbers to keep count of the loadings. Then mark in the Letters when trimming. When it needs third trim: toss in the recycle bucket. Why try for "JUST ONE MORE TIME" when you light off a 60000 psi rocket next to your head.

    For years my 300 used to like Reloader 22. Now it likes 4350, that's fine by me as it is cleaner and takes less of a charge. Any speed over 2800 seems ok in mine. Never tried lower. Using 150g Hornady Interlocks currently due to 1K bullet rebate. Add a muzzle-brake, then watch impacts :)
  17. Innovative

    Innovative Well-Known Member

    JimKirk ........

    Your experience with belted magnum calibers is common, and your thoughts are very logical.

    However, many shooters have found that their thinned brass (above the belt) eventually gets weakened enough to bulge easily with the slightest downward pressure during the reloading process. This never shows up until after the second or third firing, so most shooters assume that this symptom "only" happens when switching from one rifle to another. This is definitely not the case.

    Due to extreme recoil (and expensive ammo), most magnum shooters don't actually shoot enough rounds to reload each case more than twice, let alone keep track of how many firings their cases have "really" had. Belted cases are usually discarded long before their time to avoid problems, and it doesn't matter if you're shooting weak loads or hot "dragon killer" loads, because brass will only stretch as far as your particular handloads will be allowed in your chamber - regardless of pressure.

    Watching your chamber clearance (at the shoulder) minimizes the amount of case bulge you will experience, because you can prevent brass from getting too thin. It's easy to measure case diameter with ordinary calipers, and see how much your cases are expanding. However, measuring chamber clearance (at the shoulder) requires another method of accurate measuring. Managing brass bulge above the belt avoids 99% of "fail to chamber" or "hard to chamber" symptoms.

    - Innovative
  18. JimKirk

    JimKirk Well-Known Member

    In another thread that you may or may not have read, I believe it was called "Full length vers Neck sizing" or something along that line, I believe stated that I used a set very near to what you market as far as measuring the shoulder placement(sizing, bump). I owe my tools to a now deceased uncle who worked for NASA and the Savannh river site. What I use is a ground steel base plate, a magnetic base, a Starrett Dial Indicator .001 and a Mitutoyo Indicator .0001 and a Sinclair bullet comparator. I have been using this for 15+ yrs. You can use the comparator with the shoulder, you just have to use one that will slip over the neck of you cartridge, it is machined so it does give precise measurements.

    Jimmy K

    Attached Files:

  19. Innovative

    Innovative Well-Known Member

    JimKirk .......

    There are different tools to measure your handloads. I'm not saying that I've got the only way to do this. Just that it really needs to be done to get the benefit of longer case life and reliable chamber fit.

    - Innovative
  20. JimKirk

    JimKirk Well-Known Member

    That was not what I was saying at all.

    What I was saying was that I basically use the same tools as you, but I put it together over 15 yrs. ago using a mixture of very well made instruments(thanks uncle).

    My base plate is used just like the base of your system.

    The indicators is mounted on rod very similar, but it is magnetic just like the machinist use.

    The Sinclair hex nut looking comparators are used just like the plate on your system, a precise and repeatable hole.

    The two Indicators are far more expensive than I would have purchased on my own.

    All in all it works exactly like your system, if I had to purchase all the parts it would, it would have never came together.

    Please don't think I was arguing, I was agreeing the whole time. I am just not trying to sell mine.

    Jimmy K

    Uncle never Reloaded ... only gave me the measurement tools...
    Last edited: Jan 28, 2010

Share This Page