Friend had shoulder replacement done and is planning on shooting his 350 Legend on a bear hunt with me 6 months post surgery. The outfitter would like him to shoot a bigger bullet than what the Legend shoots but it's limited by being 0.355" versus the 0.358" that I'm shooting through a Whelen. Has anyone tried sizing down a 0.358" to 0.355"? It's only 0.003 so should be easily done and would open up a wide range of options. I understand the problems of creating/working up a load, just wondering if someone had already done something like so I wouldn't have to re-invent the wheel.

Barnes Triple shocks behave like a Bigger bullet. These are the correct dimeter already-
https://www.midwayusa.com/product/1024437359



I don't know what the heck you are hunting but if a 170g All copper hollow point won't kill it you need something bigger than a .350 legend.

I built a home made 8mm tapered squinch die, honed to baby butt smooth to take .323" down to .320"...only ..003". Made the push punch from OH 1. Used Corbins swage lube. Used a big old Herters press. They pushed easily...they looked good...the base was dead square, but they never would group to the rifle's potential. I tried Hornady 170 gr roundnoses, 150 spire points and Speer 170's. I could get a nice 3 shot group, but when I went for 5 or 10, the non concentric bullets dramatically opened the groups...from 2 moa to 4 moa using an iron sighted 8x57 J bore.

I published an article about this in the December/January 2022 issue of Handloader magazine. I purchased a sizer-die from Lee Precision, which as I recall cost $35 including shipping, and worked very well, allowing FAR more bullets to be used in the .350. The article is available free on-line: https://www.handloadermagazine.com/350-legend

I recently resized some 286 grain .366 bullets to .358 for my Whelen with a Lee sizer. I had to do it in two steps, with a .361 die as the middle-man. I have a Lee turret press; a stouter press may have been able to do it without the .361 die. 0.003 should be easy in one pass, on any press. I used both Hornady One-shot and Lee lube. I didn't notice a different between the two.

Thank you gentlemen very much. I knew I could count on the campfire to enlighten me.

I haven't had the luck mentioned above.

Reduction in stages is best to retain bullet integrity. 0.003 to 0.004 inches maximum in one pass is considered optimum to preserve bullet/jacket integrity and overall shape. No more than 0.008 total reduction. Generally speaking short, fat bullets show the least damage when reducing their diameters. Once upon a time, this was popular with RNs. for example, reducing .323 bullets to .318 for Commission rifles. In Canada and the UK, reducing .313 bullets to .308 diameter was done when when .313 bullets were everywhere.

When it comes to deformation, spitzers and BT spitzers are the worst offenders. They can bend like bananas if too much reduction is attempted in one pass. Even a 0.004 inch reduction can cause the core to come away from the jacket. I had the most problems with Sierra bullets. IMO, this was due to their thinner jackets.

Necessity often demands reduction, but if it is going to be a regular thing, it's best to use two or three dies. If possible, no more than 0.010 inches total. CH4D can produce inexpensive dies for the purpose.

I have and old drilling in 6.5x58R Sauer with a bore groove diameter of .260 and I size .264's down, they work well. I bought my bullet sizing die from C&H 4D.