I am going crazy trying to use the Sinclair bullet seating gauge!

[Quinc]

I am about to lose my mind trying to find the seating depth on my Barnard P .284. I found two bullets that measure exactly the same base to ogive. And the two fired cases I am using measure exactly the same base to shoulder. Yet using this damn tool I get two completely different measurements; 1.71 and 1.54... aarrrggghhh!!!! Can someone please tell me what I am doing wrong or give me some tips.

Thank you in advance!

 

[Lapua40X]

IMO, that Sinclair tool is crude and incapable of providing accurate results.
Trying to obtain an accurate measurement of a bullet flopping around in the free bore, IMO, is an exercise in futility.
What did you use to determine that the distance from base to ogive on the bullets was equal?

 

[savageshooter86]

<iframe width="560" height="315" src="//www.youtube.com/embed/FYmVy-VhXgM" frameborder="0" allowfullscreen></iframe>

That tool for some reason looks like it would not be precise at all

 

[ShootDots]

I know that Sinclair makes excellent loading equipment. However, their "Sinclair Bullet Seating Depth Tool" looks like it is fairly complicated compared to the Hornady Lock-N-Load one. I use the Hornady (I Bought it when it was Stoney Point) and I have been able to get pretty dang accurate readings for seating depth. Now MOST, not all, of my modified cases are formed from my chambers and made by my riflesmith. I use 4-5 random bullets out of a box, each time I load. I measure the seating depth and do my best to get a good average, usually inside 2K. Having said that, it has also been a recent phenomenon to find upwards of 4+k variations of seating depth from the same lot of bullets.. That never used to be>>>but is becoming all too common... I know this does not answer your question PE SE, but it may be the complexity of the Sinclair rig, compared to the Hornady.

 

[Quinc]

What did you use to determine that the distance from base to ogive on the bullets was equal?

Hornady Lock-N-Load Bullet Comparator. Works great, kicking myself in the arse now for not sticking with Hornady.

 

[savageshooter86]

send the Sinclair back to them. 100% satisfaction guarantee. They are great to deal with when returning an iem

 

[queen_stick]

http://www.sinclairintl.com/reloading-equipment/measuring-tools/bullet-seating-depth-tools/sinclair-bullet-seating-depth-tool-prod35491.aspx

I think the video in their product description answers the question... It ends by measuring the length of the bullet (from base to tip). Your bullet seater isn't seating the bullet by the tip, and ogive differences may be source of the difference. It also possible that the the bullets are in fact seated the same, but tip-length differences are causing erratic measurements.

do your 2 bullets measure exactly the same length base-to-ogive? If so, does your COAL measure the same from case head to ogive?

 

[Quinc]

http://www.sinclairintl.com/reloading-equipment/measuring-tools/bullet-seating-depth-tools/sinclair-bullet-seating-depth-tool-prod35491.aspx

I think the video in their product description answers the question... It ends by measuring the length of the bullet (from base to tip). Your bullet seater isn't seating the bullet by the tip, and ogive differences may be source of the difference. It also possible that the the bullets are in fact seated the same, but tip-length differences are causing erratic measurements.

do your 2 bullets measure exactly the same length base-to-ogive? If so, does your COAL measure the same from case head to ogive?

Did you read the first post?

 

[Keith Glasscock]

A .200 difference sounds like one is getting into the freebore and the other is hanging up going into the throat. Try checking the two bullet diameters one could be only .0001 larger and causing the problem.

 

[BoydAllen]

On the point of measuring the bullet to its tip, I use one bullet for my measurements, with the seating depth tool, and then load it in my first round, to the seating depth that I want, relative to the calculated touch length, measuring off of the tip of the bullet, and adjusting the seater accordingly....THEN I measure the length of the loaded round off of the ogive, with the appropriate tool, and record that, including the seating depth, and what tool was used to take the measurement. This completely does away with any issue of lack of uniformity from tip (meplat) to the point at the back of the ogive, where the measuring insert makes contact. Gauging bullets for uniformity in the distance between where the seater makes contact on the ogive, and where the rifling will touch, is a whole other can of worms...that has a direct effect on the uniformity of loaded rounds' seating depth. The quick and dirty, and probably best way to look at this issue is to use a arbor press seater to eliminate most of the die and press variables, and then measure all loaded rounds ogive to head, and note the ES of those measurements.

 

[Lostcreek]

Quinc,
I have gave up on that tool. With the same bullet and case i would get a different measurement every time. I now use a dowel rod and a sharpie. With the rod down the barrel put a mark at the end of barrel with the rod against the bolt face and to a bullet seated in the lands. Same measurement every time.

 

[tenring]

IMO, that Sinclair tool is crude and incapable of providing accurate results.

I agree, don't use it anymore. I have the Hornady comparator, but prefer the Davidson base and nose pieces sold by Sinclair. It gives me very accurate measurements.

 

[queen_stick]

Did you read the first post?

Sorry man, missed the "base-to-ogive" bullet measurement in your first post.

Based on that, I'd assume you're measuring COAL to the ogive as well

I've never used this thing, but based on other posts, I'm glad that I haven't.

 

[djtjr]

+1 I do this too one bullet take the measurement a few times you will see a paterna and maybe an outlier take an average and use that as your measurement for seating that bullet in the same brass you used. The tool takes some time but I am always always within .003 on the multiple try's. Use the metal pole to give the bullet a light tap so that it seats fully and a lot of The variation you are getting will go away.

On the point of measuring the bullet to its tip, I use one bullet for my measurements, with the seating depth tool, and then load it in my first round, to the seating depth that I want, relative to the calculated touch length, measuring off of the tip of the bullet, and adjusting the seater accordingly....THEN I measure the length of the loaded round off of the ogive, with the appropriate tool, and record that, including the seating depth, and what tool was used to take the measurement. This completely does away with any issue of lack of uniformity from tip (meplat) to the point at the back of the ogive, where the measuring insert makes contact. Gauging bullets for uniformity in the distance between where the seater makes contact on the ogive, and where the rifling will touch, is a whole other can of worms...that has a direct effect on the uniformity of loaded rounds' seating depth. The quick and dirty, and probably best way to look at this issue is to use a arbor press seater to eliminate most of the die and press variables, and then measure all loaded rounds ogive to head, and note the ES of those measurements.

 

[djtjr]

Btw then measure coal with a comparator as the base to tip oal will not be nearly as accurate between bullets. The reason you only use 1 bullet with the tool is that that 1 bullet won't have variation in the tip but others will. Use 1, find oal for that then comp it off the olive to get seating depth for all your bullets afterwards.