uxcell 1pcs Round Steel Metal Rods, 9mm x 200mm High Speed Steel (HSS) Lathe Bar Stock Tool, for Shaft Gear Drill Lathes Boring Machine Turning Miniature DIY Craft

Does not fit the crown of some barrels for psh psh alignment reasons. It's a 9mm rod, straight as could be and the machining is good.

Perfect.

Maybe I'm crazy, but I bought this as a poor man's muzzle flash alignment rod for a 10/22 rifle. (The "official" aligners can run like 60 or 70 bucks...) It did the job great for my purposes, fitting down the barrel really nicely. It was easy enough to slide in, but yet snug enough that it didn't wobble at all. One caveat is yes, these can have a millimeter or so of warp distributed over the length of the rod, meaning I could only push it in about 80 percent of the way before it started to make light contact with my rifling. But that was deeper than I needed it to go anyway. Inserting the rod about halfway and then rolling it gently through my fingers gives me a VERY GOOD idea of where my bore/muzzleflash alignment is sitting. If any of this sounds reasonable to you, it might be worth saving yourself 60 bucks to give this a try.

works great as a jump ring mandrel. good value. nice surface.

Don't expect to cut this easy.

The dimensional accuracy and straightness seem fine, but if you use it to line up your shhhhhh it's probably too short

Item is so bent that it won't roll across a flat surface. Don't recommend.

Ordered this with intent to make a 7.5mm pin, item mics .287-.290" with calipers which is under 7.5mm. should be .294-.296 but picture also says .3". It's a nice piece of metal so I plan to keep for future but isn't to spec and won't work for the reason I ordered.

Worked great for me. Used to replace a bent shaft on a model airplane motor.