Home Forums Reloading Big Game Rifles RCBS Precision Mic??

Anybody using these? Thinking about one for the 7-08 and 223. Worth the $$?

Go with the Stoney Point (Hornady now I believe). The RCBS is a good tool but you can do the same with the cheaper tool and IMO easier to operate too doing some measurments.

Good tool but concur with Joe. They are cumbersome to operate compared to the Stoney Point. I had most if not all the Precision Mics. When I got the Stoney Point I sold them all, except a 300 Win Mag which I'd gladly get rid of. Besides, the Mics are cartridge specific whereas the Stoney Point is not; much more flexible in use for all cartridges and calibers.

I've got a couple. they are very useful. not sure if they're really worth the $$ compared to the stoney point

Thanks for all the info. Will p/u the Hornady/Stony Point version someplace besides GANDER MOUNTAIN!

The precision mic is good for setting the shoulder back (head space) but it is useless in measuring how far to seat the bullet. The demo bullet that it comes with would not have the same ogive measurement as the bullet you are loading. I like mine for setting my resizing dies up, but have the stoney point for checking bullet seating depth.

It doesn't really matter that the demo bullet doesn't have the same ogive shape as the bullet you use, nor does it matter that different bullets have different ogive shapes. You are determining the distance to the lands.

The distance to the lands doesn't change when you use a different bullet, nor does the diameter of where the land nut contacts it, and that distance is measured with the Precision mic in any case, and you use the land nut to get a reading and record it.

You simply seat your bullet using the reading plus whatever distance you choose.

For me, it was easier to use than the SP tool, and I only had to find the distance once. It is worth the money if you don't have another way to determing seating depth that works for you.

Smitty of the North

I have the RCBS, my son has the Stoney Point. I got the RCBS before the Stoney Point was available (or maybe I just never heard of it). I found the nylon "bullet" a pain to work with in terms of repeating results. After many attempts, I finally settled on what seemed the most-often achieved measurement and went from there. Things have been fine from that point on and I have recorded the setting on my Forster seater to achieve the desired length with each bullet that I use. When my son started loading, he went with the Stoney Point. I really like the fact that it starts out using each individual bullet. It also seems to be more positive in establishing bullet length. I guess what I have gone on for quite some time attempting to say is that once I worked things out to my satisfaction with the RCBS, I am happy with how it works, but if I were to make a recommendation it would be for the Stoney Point for someone making an initial choice between the two. Best, John

Thanks for the correction on the precision mic. I was using it wrongly to measure bullet seating depth. Thanks for the correction. And I'd have to agree with 5sdad that the stony point was much more consistent in getting the measurements for distance to the lands.

Go with the Stoney Point bullet comparator--now owned by Hornady....it's one of the best reloading tools to come along in quite some time. Precison Mics work fine ( I have a couple of them), the camparator kit is more versatile, easier, and cheaper.


Casey

The Stoney Points are easier to use to set you seating depth but I've used both on the same rifle and ended up with the same measurements so they both work.
The Precision Mic do give you the added capability of measuring the headspace of your rifle and brass. This can give some interesting and useful results.
Also you can mix and match the RCBS Mic's a bit. Say if you have a 308 win and a 7 Win Mag tool you can use the 308 head on the 7 Mag bullet and get a repeatable length to the lands as well as using the 7mm on the 308 for a 7-08. I have several of them and mix and match them quite a bit.
So if you need the Headspace and Case measuring go with the RCBS but if you just want to measure bullet seating depth the Hornady (Stoney Point) tool is cheaper and easier. But be sure and buy the comparators that clamp onto your calipers if you want the most accurate readings, just measureing the bare cartridge isn't as accurate..............................DJ

This is only partially correct in that the Stoney Point IS cheaper and easier to use. However, they also have comparators for checking base-to-datum line on the shoulder of most any bottle neck cartridges, even that on the belted magnums which headspace on the belt. It does everything the Precision Mic does, and more, because it is not cartridge specific as are the Mics.

Yes, if one buys the Comaparator, may as well buy the Case Gage too.


Casey

what if you don't want to headspace a magnum off the belt ?? does the Hornady allow for that ?? (the RCBS allows for headspacing the shoulder on bm's -- the only reason I use it)

You beat me to it. I will echo the above post 110%.

If someone thinks the shape of the "demo" bullet matters, they need to go back and hit the books some more.

scott

Yep!!

RSY, I will refer you to a book called "Precision Shooting Reloading Guide" edited by Dave Brennan. Mine has a copyright date of 1995. Page 47, Bullet Seating Depth for fire forming, "To find the point where the bullet needs to be seated so that it is just touching the rifling, the handloader must find the true overall length (OAL) of the cartridge. Remember this length will be different for every rifle and each style/make of bullet." This section was written by Fred Sinclair and Bill Gravatt. Following your line of thinking that once you find the lands all bullets will seat to that depth is not correct. If it were true then my competition seaters whose seating stems are on the ogive of the bullet would seat all makes of bullets to the correct depth if I used only one type of bullet to set the die. The lands contact the bullet on the ogive before the bullet reaches full caliber and so do my seating dies. There are reasons why just knowing where the lands are on one bullet can't be translated to another bullet, some are very close to the same, some aren't. Your suggested reading is the afore mentioned book and Rifle Accuracy Facts by Harold R. Vaughn.Rick.

No. What I'm pointing out is that the diameter where any bullet engages the lands will be a constant value, as is the distance from the lands to the boltface.

The variation lies in: Where along the length of any particular bullet is that "land diameter" located? That is where we accordingly seat to (plus or minus your favorite number off the lands). The distance from bullet-tip-to-stern is really of no concern (except for magazine limitations).

After reading your post, again, I think we're on the same sheet of music, actually.

scott

One should ,I might add check the overall length (touching lands)as the rifle gets older as throat erosion will allow you to lengthen to compensate. I occasionally seat long on test round, chamber and recheck overall length, measure and record. Adjust the mic accordingly. Correct me if I'm not doing it right, but so far no problems. This works on single shot rifles but on some rifles the length becomes to long for the magazine.

As long as we agree that, measured with a mic or any other comparator, different bullets may measure differently when seated to the lands.Rick.