300 Win mag in an Autoloader

Quackaddict

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Hey guys, I have been asked to make some handloads for a gentlemans 300 Win Mag, he uses it for deer hunting and I plan on using something in the 180 grn weight class for a bullet. My question is what differneces ar ethere when loading for an auto? I would assume I can't use to hot a load or I risk damaging the gas system, the weapon is a BAR of some variation. What are the pressure signs for an autoloading weapon?
 

CanPopper

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Re: 300 Win mag in an Autoloader

Autoloading on a .300 Win Mag? I haven't seen too many guns that do that.

For the 180's, I've tried a whole bunch of bullets. Reloader22 works best and the optimal range is between 73.6gr to 74.4gr (for my gun). Not sure what it would be for an autoloader though.
 

Victor N TN

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Re: 300 Win mag in an Autoloader

I've never loaded 300 WM for an autoloader. A quick check of a couple of manuals don't show specific loads for an auto loader. The 2 most used are Winchester Model 70 and a Universal receiver. These don't say anything about op rod damage or anything like that. But I would be concerned about it.
 

GB300wm

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Re: 300 Win mag in an Autoloader

Reloading for an autoloader is not that much a chore. Browning does make one and it can withstand normal operating pressures associated with this round. Remember to use a small base resizing die and it's not a bad idea to crimp the loaded cartridge. RL 22 will work just fine and reloading manual data will also suffice. I would, however, stay near max of book data for proper functioning of the action. These rifles are designed for factory loads and most reloading data is on the safe side.
 

mdmp5

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    Re: 300 Win mag in an Autoloader

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GB300wm</div><div class="ubbcode-body"> Reloading for an autoloader is not that much a chore. Browning does make one and it can withstand normal operating pressures associated with this round. Remember to use a small base resizing die and it's not a bad idea to crimp the loaded cartridge. RL 22 will work just fine and reloading manual data will also suffice. I would, however, stay near max of book data for proper functioning of the action. These rifles are designed for factory loads and most reloading data is on the safe side.</div></div>

    To the best of my knowledge, there is no small base sizing die for 300WM. Just be sure to bump the shoulder back enough so that the cartridge headspaces solely off the belt.
    There are probably less than 5 semi auto rifles ever manufactured that chamber 300WM. The only one I can think of is the WA2000. Benelli makes a semi 300WSM though.
     

    Quackaddict

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    Re: 300 Win mag in an Autoloader

    I will verify again to be 100% sure on what make the gun is sometime when I see him again, but I am 95% positive it was a BAR in 300 win, why he needs such a critter to blast a fragile deer is beyond me, but I am gonna do him a favor as I have access to dies and RL-22 is a powder I want to try in my 270 anyways.

    What do you mean by headspacing off the belt?
     

    sinister

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    Re: 300 Win mag in an Autoloader

    Arms Tech SMIR .300 Win Mag based on BAR II:

    clip_image002smir.jpg


    diesmall.jpg

    Innovative Technologies Belted Magnum Collet Sizing Die.

    "Belted magnum cartridges have been around for over 50 years, and most shooters who reload them are familiar with the case bulge problem that occurs "just above" the belt. This usually happens after just 2 or 3 firings - wasting perfectly good cases. Many shooters have discovered this problem when they find their handloads begin to stick in the chamber, or when they no longer chamber at all.

    "Unlike non-belted cases, the belt prevents the case from sizing deep enough in conventional full length dies. This limits the amount of resizing, and brass is plowed rearward toward the belt. The brass builds up just above the belt at each sizing, and cases expand. Neck sizing dies don't bump the shoulder back or resize the tapered case wall. The best solution is to full length resize accurately, and use this collet die to reduce case width.

    "Our patented Belted Magnum Collet Resizing Die solves this problem and has other unique features. The top of this die is a case width gauge that shows when a little "extra" case resizing is required. This resizing die is used to eliminate the case bulge above the belt, after using your full length (or) neck sizing die. Our collet die ensures that your belted magnum ammo will always chamber properly and your cases are now able to last for up to 20 firings, even when using the hottest handloads. Our resizing die uses a collet that fits over the cartridge case until it bottoms against the belt. The case is then pressed into the sizing die. The collet allows your case to go farther into the die where it only reduces the area "just above" the belt.

    "This ONE die and collet is universal and works on ALL of the popular belted magnum calibers including: .257 Weatherby Magnum; 6.5 Remington Magnum; .264 Winchester Magnum; .270 Weatherby Magnum; 7 x 61 Sharpe & Hart; 7mm Remington Magnum; 7mm Weatherby Magnum; 7mm STW; .300 H&H Magnum; .300 Winchester Magnum; .300 Weatherby Magnum; .308 Norma Magnum; 8mm Remington Magnum; .338 Winchester Magnum; .340 Weatherby Magnum; .350 Remington Magnum; .358 Norma Magnum; .375 H&H Magnum; .416 Remington Magnum; .458 Winchester Magnum; .458 Lott Magnum and several belted wildcat cartridges. There are no extra collets to buy when resizing different calibers.

    "The U.S. Secret Service was one of our first customers.

    "So far, we've sold over 3,100 of these dies. Unfortunately the high cost of manufacturing usually requires us to build a waiting list before each production run. These dies are in stock, so . . . . if you would like to get one, don't wait too long."
    http://larrywillis.com/
     

    DBohn

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    Re: 300 Win mag in an Autoloader

    Benelli's R1 comes chambered in .300 Win Mag and I've reloaded for it without any issues. I stayed in the realm of safe loads in the manual though and never tried working up to find a max charge.
     

    ChadTRG42

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    Re: 300 Win mag in an Autoloader

    Yes, Browning makes/made their BAR in many common hunting calibers, including 300WM, 30-06, 243, 270, etc, etc. (I hunted with a guy that had many BAR's.)
    I would not load max loads in it, since it is a semi auto. Pressure signs will be shiney spots on the case head and/or ejector marks on the case head. These rifles are not known to be tac drivers, so if you get it shooting 2"-3" or less at 100 yards, that's pertty good. R22 is a good choice for the 180 bullets.
     

    Quackaddict

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    Re: 300 Win mag in an Autoloader

    Thank you chad, I hadden't planned on working to hard on these reloads to get them to shoot, he shoots in the brush and an average shot is 50-75yds, even 3MOA is plenty for that kind of shooting. I can make ammunition with a premium bullet for less than he can buy cheap ammo for, that is the driving force behind this. I figure I can save him about 20 bucks a box compared to what he is shooting now.
     

    GB300wm

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    Re: 300 Win mag in an Autoloader



    To the best of my knowledge, there is no small base sizing die for 300WM. Just be sure to bump the shoulder back enough so that the cartridge headspaces solely off the belt.
    There are probably less than 5 semi auto rifles ever manufactured that chamber 300WM. The only one I can think of is the WA2000. Benelli makes a semi 300WSM though. [/quote]

    RCBS makes a small base resizer

    http://www.midwayusa.com/viewProduct/?productNumber=139390
     

    mdmp5

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    Re: 300 Win mag in an Autoloader

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: GB300wm</div><div class="ubbcode-body">


    RCBS makes a small base resizer

    http://www.midwayusa.com/viewProduct/?productNumber=139390</div></div>

    Wow, how about that? I learn something new every day. I am so conditioned to Redding dies that I missed this one. Thanks for the info.
     

    mdmp5

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    Re: 300 Win mag in an Autoloader

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Quackaddict</div><div class="ubbcode-body">I will verify again to be 100% sure on what make the gun is sometime when I see him again, but I am 95% positive it was a BAR in 300 win, why he needs such a critter to blast a fragile deer is beyond me, but I am gonna do him a favor as I have access to dies and RL-22 is a powder I want to try in my 270 anyways.

    What do you mean by headspacing off the belt? </div></div>

    If you look at a 300WM case, right above the head, there is a thick rim; this is the belt. Belted magnums headspace off this belt, in other words, it prevents the case from moving forward in the chamber. The thing with belted magnums is that you can headspace off the belt, or when the case is fireformed to your chamber, it can headspace off the shoulder. Typically, the accuracy is better after fireforming the brass to headspace off the shoulder, but I am sure there are exceptions. But in handloading, it is much better to headspace off the shoulder, because you don't work the brass as much when sizing down a tad as opposed to well over 0.002" of bump. For an autoloader though, I would personally bump that shoulder back enough so that the case truly headspaces off the belt so you don't run the possibility of a jam.