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Bullet pointing for FTR


blaser308

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If you serious you point...

It does improve group size / verticals by reducing the spread range of BC by uniform tips

Plus worth about 0.75 moa reduction in elevation

It's in effect the equivalent of launching bullets about 120 fps faster for a 155

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If you get the shooting shed pointer you won't regret it..

some trim the meplat first some don't.. I am in latter

Trimming reduces the BC and creates bigger weight variation and is very time consuming

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  • 2 weeks later...
  • 2 months later...
  • 2 months later...

Recently bought a Montour county meplat uniforming tool to trim over all Length of batched bullets along with uniforming the hollow points before pointing them anyone else using this piece of kit also how much are you guys closing 200g hybrid bullet meplats when pointing @ 50% or tad more has anyone found closing the meplats more than say 60-70% causes accuracy/vertical issues at 1000y ranges.

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has anyone found closing the meplats more than say 60-70% causes accuracy/vertical issues at 1000y ranges.

 

Can't comment on 30-cal Hybrids, but I found this with 155gn Scenars in the early days of FTR. Overall, I've found trimming/pointing has worked very well with some bullets, but seems to have little effect on others. The only way you find out which category a bullet falls into is through trial and error.

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Some where out there on the internet Bryan Litz has published data on the BC gains after pointing various bullets, all I can remember is the 180 gr 7mm Hybrid has one of the biggest BC gains.

 

From 3 to 7% additional BC value Ian (Litz). The amount depends (obviously) on the original meplat diameter / area and how much the pointing reduces that, and (less obviously) on calibre. The smaller the calibre for any given area reduction, the greater the gain, as meplat area has to be taken in the context of the bullet's overall frontal section. So, a .224" bullet which sees a large meplat reduction will likely get somewhere around the 7% improvement, a 30 or 338 or 50 gets least.

 

The trend in recent years is for larger meplats (Sierra aside which is now factory pointing nearly all its MatchKings it seems). The Lapua Scenar Ls are very large for example and the Berger Hybrids bigger than those on older VLD models. This is because the reason for retaining a meplat at all, it to provide a surface for the nose forming die's ejector pin to bear on. It has been found that larger meplats not only reduce production disruption and costs caused by bullets stuck in the die / broken ejector pins, but the finished bullets are more consistent and therefore perform better at the cost of a small loss in BC.

 

As a generally 'cautious pointer' using the Whidden dies, I assume +5% on the Litz calculated BC of my 224 90s, and +3% on 30s, 3-4% for 6.5s and 7s.

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Laurie, I also Have found adding 3% G7 values with the 30 cal pointed 200g hybrid for wind + drop calculations very good have heard overpointing bullets most likely to decrease accuracy as the bullet base can be slightly deformed when increased pressure applied to almost close bullet hollow point so as rule when pointing 30 cal heavies would closing hollow points by 50% be the norm, thanks for replies.

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  • 4 months later...

I was advised to check base to ogive length during pointing and stop when it started to change i.e. compressing base. This is a long way before a bulge appears below the tip it seems!! Scenars quite difficult to point a lot as material is v hard and base starts to deform quite early. This is why some ranges ban them due to their armour piercing ability!!!!

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