Reloading .300 Win. Mag.

.44 · March 29, 2002, 02:46 PM

Hey all, I'm a newbie to reloading and I've got a couple of questions reguarding this.

First of all, what is the length you should trim the case to? My caliper papers say to trim it to 2.610, while it seems that others use 2.620 (the maximum overall length)-which is right? And with my particular bullet (150 gr. Speer spitzer soft point) they seat it at 3.330 while it seems common to seat (with bullets of this caliber and weight) at 3.340-which is right? Also, how close must you be to these measurements? I trimmed my cases about .003" short and seated my bullets about .005" shorter than what they seated them at-is this close enough?

And finally, I would like a load (with my 150 gr. Speer and my IMR 4350) that is not hot, but is along the lines of a .300 win.'s power. My current load is 69.0 grs. of IMR 4350 behind the 150 Speer, and I would like something with a bit more oomph-as this is only 30-06 power.

Any responce is GREATLY appreciated.-Ben

sricciardelli · March 29, 2002, 06:07 PM

http://stevespages.com/page8.htm

ms1200 · March 29, 2002, 11:55 PM

trim length for the .300 win mag. is 2.610 max is 2.620. which is right? as long as you are not over max you will be alright. keep in mind though that cases will grow from fireing and 2.610 will mean trimming less often. best accuracy is often acheived by seating the bullet out closer to the lands in your rifle. a good tool to do this with is the stoneypoint oal gauge.this tool will measure your chamber from the base of cartridge to where the bullet ogive contacts the lands. to do this you will need the oal gauge,a stoney point modified case that scews onto the oal gauge,and their bullet comparater with proper calibre incert. you need to take a measurement for each different bullet you use as they are all constructed differently. you do not want the loaded round to contact the lands. i start at .020 off the lands and work it out slowly untill i find the sweet spot. your magazine may limit how far out you can seat.......my particular rifle is at its best with 180-200gr. bullets & H4831. you will find that many rifles have a preferance to what you feed them. a good load in 1 might not shoot good in another. for me the searth for the perfect load is half the fun............as for measurements being "close enough" the more uniform you can make each and every round the better your ammo will be...........wishing you safe and good shooting

Tol · March 30, 2002, 12:57 AM

I hope this is not rude of me and am hoping that .44 will find any answers interesting too.

How far down can .300 Win Mag be loaded and still be accurate.

Are there inherent safety hazards to a rifle load that is too light? So much chatting is done about super-hot loads that I suppose I never have it any consideration.

For instance, could a .300 Ultra Mag shoot a 100g bullet loaded down to 2700 fps? Seems like a way to make a big magnum do double duty on coyotes.

How well does .300 WM handle very heavy bullets? ie; 250g

Thanks fellas, and .44 for starting this thread.
This is something I'd wondered buy didn't find addressed in reloading books.

Stonesheep · April 2, 2002, 11:35 PM

It seems to me that "downloading" a 300 Ultramag might be akin to using a F-1 Ferrari to drive in the slow lane...Just kidding!!! Most reloading books, and the reloading I've done for my 300 Win Mag, show that if loaded to near max it provides the best accuracy. If it is a 'flinch' issue and the gun is not comfortable to shoot, it doesn't make you any less of a man to possibly buy a 308 or 30-06, if you wish to stick to .308 calibre. I personally love shooting my 300 WM; Winchester Super Grade, 26 inch barrel non-muzzlebreaked barrel, fairly heavy weight. Shot 60 rounds this last weekend. Right now I'm working on a new load, 200 grain Match Kings with 72 grains of Reloader22. Haven't got to chrony yet, having only went to the range once so far this spring as the temperature is still hitting -26 dg Celcius at night...the joys of living up North. My pet load is a 190 gr Hornady BTSP stoked to 174 grains of Reloader22, 3000 fps. Another load I'm playing with is 150 gr Ballistic Tips, 73 gr of IMR4350; and 130 gr Barnes-X at 76 gr Imr4350.....please warm up SOON. Really want to clock the 130 grain Barnes - they should be spitting out the end at around 3550 fps; that would be a crazy coyote load. My rifle seems to be preferential to the heavier loads, 180 grain and up. Took a moose and a black bear last fall with the 190 grain load and all I can say is that that bull went down RIGHT NOW...perfect.

Stonesheep · April 2, 2002, 11:39 PM

Sorry for the double-post, but forgot something....totally want to try a 250 grain Barnes Original load......that would swack a moose or elk really nice. I do believe that a faster twist barrel might be needed for that application, but I still want to try. Guess I now have to explain to fiancee why I am ordering more bullets, sigh.

March 29, 2002, 02:46 PM	#1
.44 Member Join Date: December 14, 2000 Posts: 15	Reloading .300 Win. Mag. Hey all, I'm a newbie to reloading and I've got a couple of questions reguarding this. First of all, what is the length you should trim the case to? My caliper papers say to trim it to 2.610, while it seems that others use 2.620 (the maximum overall length)-which is right? And with my particular bullet (150 gr. Speer spitzer soft point) they seat it at 3.330 while it seems common to seat (with bullets of this caliber and weight) at 3.340-which is right? Also, how close must you be to these measurements? I trimmed my cases about .003" short and seated my bullets about .005" shorter than what they seated them at-is this close enough? And finally, I would like a load (with my 150 gr. Speer and my IMR 4350) that is not hot, but is along the lines of a .300 win.'s power. My current load is 69.0 grs. of IMR 4350 behind the 150 Speer, and I would like something with a bit more oomph-as this is only 30-06 power. Any responce is GREATLY appreciated.-Ben

March 29, 2002, 06:07 PM	#2
sricciardelli Senior Member Join Date: August 13, 2001 Location: Montana Posts: 489	http://stevespages.com/page8.htm __________________ http://stevespages.com/page8.htm Last edited by Johnny Guest; April 1, 2002 at 12:12 AM.

March 29, 2002, 11:55 PM	#3
ms1200 Senior Member Join Date: March 17, 2002 Posts: 133	trim length for the .300 win mag. is 2.610 max is 2.620. which is right? as long as you are not over max you will be alright. keep in mind though that cases will grow from fireing and 2.610 will mean trimming less often. best accuracy is often acheived by seating the bullet out closer to the lands in your rifle. a good tool to do this with is the stoneypoint oal gauge.this tool will measure your chamber from the base of cartridge to where the bullet ogive contacts the lands. to do this you will need the oal gauge,a stoney point modified case that scews onto the oal gauge,and their bullet comparater with proper calibre incert. you need to take a measurement for each different bullet you use as they are all constructed differently. you do not want the loaded round to contact the lands. i start at .020 off the lands and work it out slowly untill i find the sweet spot. your magazine may limit how far out you can seat.......my particular rifle is at its best with 180-200gr. bullets & H4831. you will find that many rifles have a preferance to what you feed them. a good load in 1 might not shoot good in another. for me the searth for the perfect load is half the fun............as for measurements being "close enough" the more uniform you can make each and every round the better your ammo will be...........wishing you safe and good shooting

March 30, 2002, 12:57 AM	#4
Tol Member Join Date: November 21, 2001 Posts: 92	I hope this is not rude of me and am hoping that .44 will find any answers interesting too. How far down can .300 Win Mag be loaded and still be accurate. Are there inherent safety hazards to a rifle load that is too light? So much chatting is done about super-hot loads that I suppose I never have it any consideration. For instance, could a .300 Ultra Mag shoot a 100g bullet loaded down to 2700 fps? Seems like a way to make a big magnum do double duty on coyotes. How well does .300 WM handle very heavy bullets? ie; 250g Thanks fellas, and .44 for starting this thread. This is something I'd wondered buy didn't find addressed in reloading books.

April 2, 2002, 11:35 PM	#5
Stonesheep Member Join Date: March 14, 2001 Location: N58-48, W122-41 Posts: 75	It seems to me that "downloading" a 300 Ultramag might be akin to using a F-1 Ferrari to drive in the slow lane...Just kidding!!! Most reloading books, and the reloading I've done for my 300 Win Mag, show that if loaded to near max it provides the best accuracy. If it is a 'flinch' issue and the gun is not comfortable to shoot, it doesn't make you any less of a man to possibly buy a 308 or 30-06, if you wish to stick to .308 calibre. I personally love shooting my 300 WM; Winchester Super Grade, 26 inch barrel non-muzzlebreaked barrel, fairly heavy weight. Shot 60 rounds this last weekend. Right now I'm working on a new load, 200 grain Match Kings with 72 grains of Reloader22. Haven't got to chrony yet, having only went to the range once so far this spring as the temperature is still hitting -26 dg Celcius at night...the joys of living up North. My pet load is a 190 gr Hornady BTSP stoked to 174 grains of Reloader22, 3000 fps. Another load I'm playing with is 150 gr Ballistic Tips, 73 gr of IMR4350; and 130 gr Barnes-X at 76 gr Imr4350.....please warm up SOON. Really want to clock the 130 grain Barnes - they should be spitting out the end at around 3550 fps; that would be a crazy coyote load. My rifle seems to be preferential to the heavier loads, 180 grain and up. Took a moose and a black bear last fall with the 190 grain load and all I can say is that that bull went down RIGHT NOW...perfect.

April 2, 2002, 11:39 PM	#6
Stonesheep Member Join Date: March 14, 2001 Location: N58-48, W122-41 Posts: 75	Sorry for the double-post, but forgot something....totally want to try a 250 grain Barnes Original load......that would swack a moose or elk really nice. I do believe that a faster twist barrel might be needed for that application, but I still want to try. Guess I now have to explain to fiancee why I am ordering more bullets, sigh.