300 WSM Seating Depth / Coal

[speeders]

I just bought a Remington 700 300 WSM. I am new to loading this calibre and have a few questions in regards to Seating depth. I'm planing on shooting 168 gr ballistic tips. I figured out distance to the lands at 2.913. I tried a dummy round at 2.885 to start and it is still too long to fit in the mag. In the past with my Remington's shooting BT's I found .010 to 0.020 has been the sweet spot for shooting close to 0.5 moa. That was with my 22-250, .243, 25-06 and 300 WM.

My trouble now is the mag length. Looks like I am going to have to start seated in at least .060 to .070. I have found in the past that I usually get erratic groups.

I have been doing as much reading as I can. Sounds like the 300 WSM isn't as fussy and need to be seated super close to the lands?

Anyone have any tips or experience that they can share.

Thanks.

 

[Shortmagman]

I have loaded the 300WSM for about ten years and I have found that with most bullets seating close to the lands is not always necessary. With my two guns(Winchester Model 70, Ruger Mark II) I have shot many different bullets from Sierra Match, Nosler Accubonds, Nosler BTs, Nolser Partitions, Berger VLD's, Barnes TTSX, and Barnes TSX's, and the only bullets that I shoot close to the land was the Bergers.

Because the Winchester allowed me to get the Berger up close, I was able to and they shot well. However, my Mark II with a shorter mag also shot the Barnes TTSX's very well .050 to .070 off the lands. The Nosler Accubonds, and Partitions shot great in the Winchester without getting them close.

I would try the Bt's at the length that they fit the mag and see what happens. You may find that they shoot great as I did with the Nosler Partitions in my Model 70.

 

[speeders]

Thanks SSM. I'm gonna load a few different combinations this weekend and head to the range.

 

[baldhunter]

I wouldn't worry too much.My Remy. groups the best @ 2.850 with 165gr Nosler BT's or Hornady Interbonds @ 200 yds.Closer to the lands it was shooting tight @ 100yds,but @ 200yds,it wasn't.Seated my bullets a little deeper and she shot tight @ 100 and 200yds.Play with it and see what she likes the best.

 

[Deleted member 46119]

I've never tried to put a handload round in the mag of my 300WSM. IMHO, strictly for factory/hunting rounds.

For my 208 A-Max load, best is .005 off the lands. I don't have my notes with me.

I have to release the bolt to remove an unfired round. Ok by me.

 

[speeders]

Baldhunter, what are you running for powder.

Thanks in advance.

 

[baldhunter]

Winchester 760,H414 is the same powder.It is giving me the highest velocity with excellent groups.Other powders I have tried with good results are,Ramshot Hunter,Reloader-22 and IMR-4350.Heck the 300WSM is not very picky.

 

[varmintH8R]

I have the same mag length constraint (I think anyone in a SA does) and have been able to get pretty good accuracy with 168 Nosler ABs seated to a COL about 5 thou shorter than mag length. I also shoot 168 Barnes TTSXs in this rig as they tend to prefer being 30 to 70 thou off the lands.

Worth noting I am certainly not a competitive benchrest guy! I get about 0.85 inch average with my best load in either above bullet, and nothing more (Winchester M70)

I have had good luck with IMR 4350 and WIN 760 for powder.

 

[tweek1142]

im shooting the 165 NBT with 68gr. H4831sc in my remington 300 wsm with excellent results. My rifle also likes the 180 NBT with 66gr. H4831sc with a COAL of 2.910. the 165 COAL is 2.905. both these loads are .5 groups at 100. When it gets warmer out i will be trying both these loads out at 300-750 yds. but until then i'll just keep experimenting.