Meplat Trimming and bullet pointing

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accumark

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I have been doing some long range shooting for a couple years now and find my self OCD with load development and reloading, I do complete brass prep from turning outside necks to annealing, primer pockets, flash holes, and once rounds are loaded I spin them for concentricity. Now I am looking for the 1 last thing I think that will complete the trilogy, how many Nutz here trim the Meplat of their bullets and then use a bullet pointing die to finish them up? I would like to hear Pro's and con's if any and people thoughts and this topic! Thanks in advance I look forward to hearing back Jim. I will be doing the for my long range 338 edge's and a 300 wn which get used out to + 1600 yards.
 
If you shoot for medals where 0.1 mil of vertical counts, pointing may have merit. Otherwise, few hobbyists claim a miss was due to a BC anomaly. Better value spending time on your elbows than at the bench. The best OCD to have is that for value of time.
 
Wow. You should contact the military and ask them if they need someone like you to custom load for sniper and special forces units. You could have fun and make money at the same time.
 
Now I am looking for the 1 last thing I think that will complete the trilogy, how many Nutz here trim the Meplat of their bullets and then use a bullet pointing die to finish them up?
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As per Brian Litz on 6mmbr website, he does not find it necessary to trim. His credentials and successes would validate his belief.
 
I believe the meplat has something to do with aerodynamics, because a sharp pointed geometry will provoke turbulence in front of it, but I'm not sure ... "mécanique des fluides" and "aérodynamique I & II" classes are decades behind me. I remember though, a cone facing in the stream, has a bigger drag coefficient then a half sphere facing the same way. I may be wrong on this, but it's worth looking into it if you're determined to go ahead with your project.
 
both meplat trimming bullet pointing and measuring the length from ogive to bullet base make a difference, with the critical length measurement I have seen articles by Mr Litz saying 2 thou difference is huge it will cause different pressures causing point of aim as well as changes in your over all es. I set up my Labradar ever time I am shooting be it range of out long range.
 
The Canadian Fclass team must trim and point there bullets. This might tell you something... I started doing that last year and noticed a difference. It is a lot of work but worth it in my opinion.
 
POINTING the bullets doesn't make them more accurate, it increases the Ballistic Coefficient. Increasing the B.C. decreases "wing drift" at long range and will make reading the wind more forgiving. At long range, with excellent reloads, an F class shooter (or a top T-R shooter) can hit the V - Bull without much difficulty IN ZERO WIND. Now, add a fishtailing wind, fluctuating from 10-20 MPH and that same shooter will struggle to keep them in the 5 ring, never mind hitting the V. The increased B.C. will make his ERRORS IN READING THE WIND much more forgiving. TRIMMING a pointed bullet actually DECREASES the B.C. SLIGHTLY but it will make the bullets more consistent because they're all trimmed to the same O.A.L. plus providing the same point shape. You can POINT without trimming and get better LONG RANGE results. TRIMMING is like adding a wee bit of icing to the cake.
 
I've played with it a bit, still gonna do more of that next season now that a couple other things are sorted out.
So far I think trimming makes a slight accuracy difference, some BR guys seemed to figure that out long ago. As to the pointing, I've not really seen a BC difference as in something that would show any vertical point of impact difference, yet, I'll play with point angle some more. I trim and point on my toolroom lathe, this coming season I'll definitely trim pretty near everything, as to pointing I'll decide if I put the extra time into it when I get there.
 
I doubt you'd notice any difference with pointing until at least 600 and preferably 800. Then you'd have to try both trimmed and non-trimmed at the same distance in the same WIND to verify.
 
Kraco said:
I believe the meplat has something to do with aerodynamics, because a sharp pointed geometry will provoke turbulence in front of it, but I'm not sure ... "mécanique des fluides" and "aérodynamique I & II" classes are decades behind me. I remember though, a cone facing in the stream, has a bigger drag coefficient then a half sphere facing the same way. I may be wrong on this, but it's worth looking into it if you're determined to go ahead with your project.
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over the speed of sound you throw that out, look at subsonic aircraft vs super sonic aircraft. 747 and an f/18 for example. the meplat is there for a few reasons, but mostly because of the handling before it starts traveling down the barrel. firstly, its easier to make a fairly consistant meplat in a production environment than a perfectly centered sharp point. if the point is out of center, the bullet wont fly consistantly. next they have to ship it, so it has to survive packaging and transport which is hard with a soft copper or lead point.

finally, it might have to survive being banged around in a magazine in a semi auto then rammed up a feed ramp before firing. a bit of inconsistancy on a meplat is much less detrimental than a slightly out of center sharp point.
 
scott585 said:
over the speed of sound you throw that out, look at subsonic aircraft vs super sonic aircraft. 747 and an f/18 for example. the meplat is there for a few reasons, but mostly because of the handling before it starts traveling down the barrel. firstly, its easier to make a fairly consistant meplat in a production environment than a perfectly centered sharp point. if the point is out of center, the bullet wont fly consistantly. next they have to ship it, so it has to survive packaging and transport which is hard with a soft copper or lead point.

finally, it might have to survive being banged around in a magazine in a semi auto then rammed up a feed ramp before firing. a bit of inconsistancy on a meplat is much less detrimental than a slightly out of center sharp point.
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It has been shown that nose damage is far less detrimental to accuracy than one might imagine. The reason is that the bullet is spinning at very high speed. Thus any asymmetrical damage is spread evenly around the air flow over the bullet because that damage is presented to all 360 deg of the air flow surrounding the bullet.
 
If you'd like a better explanation of both processes and the results of their usage, go to the website for WIDDEN TOOLS. He is a competitive shooter. Also there is a good report on the 6MMBenchrest forum.
 
If you have a .5 moa load it will make a difference, if you dont its worthless as it will not add any
accuracy advantage.
 
both my edge's can shoot better than I and I beleive are in the .5 moa average I have also come to understand the need to measure base to ogive which is said to be on the list of importance changes in length have a bearing on pressure, for those in the know please comment Thanks.
 
Trimming and pointing and quickly becomes steps of the past... Most major match bullet manfs are doing these steps for you.

Sierra has been pointing many of their MK bullets now and the job is done very well.... certainly I can't do any better.

Hrn is also pointing their BTHP. Nosler new RDFs are manf to a near spear tip.

Hrn and Sierra are using poly tips in more and more match bullets.

Berger has done a very nice job of making smaller meplats but still not quite pointed like the others. In some cals, the J4 jackets can get distorted with a heavy point so most will just "touch" up the meplat to ensure consistency vs itty bitty hole.

If there are long range benefits in increasing BC, it has got to be small cause I shoot pointed and unpointed (same bullet) and just doesn't make a big difference. The touch up to make all tips consistent is likely more for my piece of mind then anything else.

But with newer choices good to go out of the box, us OCD types are going to have to look elsewhere for the magic solution.

Jerry
 
As an OCD person who has not seen or done this I have to ask;
If you are trimming the bullet are you not removing mass?
And I assume some bullets require more trimming than others so how do you equalize the mass between bullets?
Personally I can't wait for my skill set to be at the point where this would be a concern, lol...
 
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