300 Win Mag for 1000yd Silhouette Shooting

[John Boy 6]

I enjoy shooting long range to 1000yds.  Thus far, it all has been done with single shot BPCR rifles at paper and gong targets.

Was at a Ridgway RC meeting in PA and won a Mossberg 300 Win Mag.  Ridgway has a 700-800-900-1000 yd Silhouette range and instead of spending the big bucks for a turn bolt smokeless rifle - the Mossberg will be it.  I mounted a Hi-Lux M-1000 scope on the rifle, fiddled with a bore sighter getting equal elevation and windage adjustments and then started making reloads with 150gr - 168gr - 170gr - 180gr and 220gr bullets.  Am finished with the ammo and trajectory tables for each batch of rounds, now the rifle & loads need to be dialed  in at Central Jersey for 273yd (equal to 250 meters) scope settings.  Once I get this done for each of the rounds by bullet weight, I can set the auto dial up Camputer settings.

Next work step when the weather breaks - drive up to Ridgway, spend a week there and fine tune the Camputer auto settings at 250 - 300 - 400 - 500 meters ... then compute and test the difference in Camputer settings from meters to yards at 700-800-900 and 1000yds ... plus determine which bullet weight reloads are going to provide the better groups.

And for the good of the order ... Winchester 300 Win Mag brass SUCKS!  Out of 100 cases - the extrusions on the necks for 55 cases were split and the brass looked like spaghetti.  Contacted Winchester Olin customer service after calling every day for a week - to send the brass back for replacements.  This whole process has been a month and a half and still haven't received the compensation check.  But I found a vendor on eBay selling once fired so I ordered 250 cases.  They are Federals and the brass is excellent but work was needed on them because the original ammo was probably military sniper rounds and the webs were too large and wouldn't chamber in the Mossberg.  So the cases were FL sized - web trimmed - case length trimmed - cleaned in the rotary tumbler and ID of necks chamfered  before any reloading started.  Work was worth the effort because the brass is now up to snuff for future use with excellent cases

[BullzeyeNJ 104]

Take a look at the Peterson Cartridge company 300 win mag brass. At the moment they are not making any but production should be back in a couple months. My friend has some in 300 win mag and it's very , very consistent overall. Better then anything else out there. It's worth the wait. 

[T Bill 649]

Everglades Ammo and Brass Bombers sell 300WM once fired Milsurp brass.  Lake City is mostly Federal Cartridge.  Best I have heard is Norma and RWS, with RWS being the king.  In fact, so tough most use special dies from Innovative Technologies (Larry Willis) to stretch reloads to double digits.

[John Boy 6]

Etsy has once fired 300 Win Mag brass for $30 per 50.  Other vendors are in the $43 per 50

 https://www.etsy.com/listing/593207873/300-win-mag-once-fired-military-brass