Bullet Pointing / Trimming for Long Range - Experiences?

358Rooster

358Rooster

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I should have pulled the trigger on this a very long time ago. I think it's worth doing for stuff way out there, especially way out beyond 1,000.

From those who have pointed and/or trimmed meplats, what are your experiences and which systems have you used? And I think it's fairly evident that I'm talking about open tip bullets and not lathe turned or bullets tipped with an insert. Comments such as "just use A-Tips or Cutting Edge bullets" are pointless for this query.

Thanks guys,
Rooster
 
F-Class shooters have been doing both for a long time for OTM bullets. The consensus is that trimming meplats is a waste of time and effort, however, sorting base to ojive or OAl lengths then pointing those sorts does give a measurable benefit at the longer ranges. Most of us do not bother for 500 meters but do for 900meters/1000 yards.
 
I think it depends which bullets you're wanting to do this with. As I understand it, you get a bit of a BC bump as well as a slightly more consistent BC. I just don't honestly know how much it's done these days. Aside from lathe turned bullets and tipped bullets, lots of the better bullets these days (all the Berger Long Range Hybrid Targets) are coming pointed from the factory. Obviously if you already have a ton of OTM bullets that can benefit from pointing and trimming then it might be worth investigating a bit more.
 
Well…I played the game and went down the rabbit hole…in the quest to squeeze out more accuracy I purchased a HOOVER metplat trimmer. Very well built hand powered little unit. Was buying large quantities of Sierra MK .308 cal 168g and even though they shot extremely well @ 850 yards I wanted to see if I could improve performance by trimming after reading an article in some precision shooting related magazine that made reference to uneven tips on open top match bullets. And when I looked at the Sierra match bullets and the Lapua Senars closely they DID have irregular tips !! So I started trimming and testing, wore off my finger and thumb prints in the process of spinning that little knurled handle. lol….absolutely no significant change in accuracy out of 3 separate rifles, all heavy barrels and with Nightforce optics. TRG22, REM 700, Tikka Varmint…
Then out of curiosity I tested to see if I cut away a few thousands more that it might enhance expansion in the event I used it on a trespassing coyote. There was a slight but noticeable improvement in expansion.
AND THEN… I read an other article that actually said that the slight irregularities at the top somehow enhanced accuracy!!!!
It was a long drawn out ballistics theory explanation that in spite of having a strong science/physics background I could not truly comprehend or accept…similar to how some people still think the earth is flat.lol. That article took the wind out of my sails because it reflected what I was seeing and not reaping any benefits from the effort put into it. Other efforts for accuracy paid dividends eg. Neal Jones benchrest dies, arbor presses, and other toys and tools ordered from Sinclair International. No regrets, the little trimmer is still bolted to my reloading table. It’s cute and it reminds me that I gave it a try and it didn’t work out. That’s life, not everything pans out the way we wish it should. But I don’t want to discourage anyone out there to make/not make this and other discoveries on their own time and on their own dime.
For my 3cents worth from 60 years of reloading and shooting experience, projectiles have come a long long way and your top 5 premier bullet makers turn out world class match product that you can take out of its box and put it directly on top of your prepped, primed, powdered case and gently pull down the lever. Bill
 
Thanks for your input, fellas. I appreciate your experiences with this.

The biggest thing weighing on my mind at the moment is squeezing every last bit out of .338 Berger OTM's for Ko2M. We have a pile of them - some older with ugly tips, and some of the newer lots which have much better tips. We've had reasonably good success in the past, but competing with 375 EnABLERs with turned bullets that everyone else seems to have gone to, it's either join the herd or improve on what we already have. And I detest joining herds simply to be in the herd....

Seems to be that those I've spoken to agree with your comments above, that trimming has very little effect, but pointing does show a small percentage of BC and uniformity benefit. Even a small percentage matters when trying to get out beyond 3km where seemingly every micron is amplified. It's an altogether different game.

Rooster
 
I used the Whidden die to point some 142gr Matchkings, after I shortened the bullets slightly , so loaded rounds would fit in my magazine. They shot fine, but no real difference from unpointed bullets.
 
To what max distance? I can see that small, single digit percentages would be very difficult to identify on a small scale, but stretch that scale out to three times the 'normal' scale, I would think those percentages would become more apparent.

Curious, Stubblejumper, how much did you trim off? Just enough to square the mouth and take care of the jagged bits, or more than that to hit a certain overall length? Do you happen to have any photos?
 
I need to find a way to somehow get paid going down the rabbit holes that I do...:LOL: I ran across an interesting thread (one of many, actually) about bullet sorting on the Accurate Shooter forum. Particularly interesting to me is post #67. Now, I fully acknowledge that there is a reasonably high likelihood of confirmation bias on my part, but I do think the fella that posted this response was quite measured.

If you're interested at all, the thread at the link below is quite a good read.

https://forum.accurateshooter.com/threads/bullet-sorting.3990793/page-4

Rooster
 
Just on the back of an envelope: Let’s say a Berger 300gr OTM has a BC variability of 1.2% (SD) and an average G7 of 0.430 (From Litz’ Bullet Data). I don’t see Litz has anything posted for that bullet on variability, but 1.2 is pretty standard for heavy-for-caliber Bergers.

That will induce a BC dispersion of (0.430+/-0.012*2*.430) = 0.420 to 0.440.

Starting those at 3050fps (what I get from my 338 EnABELR) At 2000m and 1122ft dalt will induce (21.9 mrad vs 20.9mrad) a full mil of vertical dispersion, or about 2m.

If you could cut that in half with pointing to 0.6% (About what the CE and best cup/core bullets get) you would see 0.425 to 0.435 and thus (21.7 mrad - 21.2mrad) =0.5 mrad =1m vertical.

If I had a lot of OTMs, yeah I’d try pointing.

You could test if it is working with a few groups even at 1000m, as long as you tracked the velocity well enough. Do 20 rounds pointed and 20 rounds not, correct for velocity, and then compare the vertical. Then make a call if it was worth the time.
 
Thanks for the detail, Harwood. This is precisely what my brain worm has been chewing away at. I've located a few Whidden pointers, just waiting on responses regarding the appropriate insert & sleeve now.
 
The problem I see is that you end up uniforming things below the threshold of the system and the medium through which the projectile must pass.

Velocity differences will certainly play a factor at extreme ranges, but we all know that.

What everyone seems to ignore is the atmosphere ... which is not at all homogenous. There will be all kinds of atmospheric differences over the course of a 3000m flight and those will add up to way more than the maybe 1% or 0.5% difference in BC gained by pointing bullets.
 
Tried it and actually ended up with problems.. didn't really see much benefit on target so stopped. Make sure the pointing sleeve supports the bullet precisely so no distortions can occur.

I now run Sierra new gen bullets which come pointed out of the box, shoot amazingly well ..... so I leave it to Sierra to give me all the bullet can deliver

Jerry
 
I tried pointing , sorting and spinning bullets for concentricity for a bit, this would have been about 30years ago.
On the advice of my dearly departed dad , we did a series of tests with 10 shot groups using logged bullets and shooting them after recording which bullet was picked .one person logging the Data and the other shooting the cartridge without knowing which bullet he was shooting - meplat pointed or unpointed.
My shooting buddy and I gave up after 20 rounds each because we could see no difference in the group sizes or concentrations of pointed or unpointed bullets . Shooting was done at 500 meters . Bullets were 6.5 and .30 Match Kings
Cat
 
I use a meplat trimmer for my Giraud and Whidden pointing dies, shooting in F-TR. Our long range 1000yds is basically ELR mid-range.

By Litz, the trimming reduces BC as you increase the area of the meplat (but make it more consistant), while pointing increases the BC by decreasing the meplat area - the overall increase in BC is small, maybe 2-5%, depending on original meplat size & bullet OD. My trimmed bullets are arbitrarily sorted into 3 groups - no touch, light tough, heavy touch, then pointed. The reason I continue to point bullets is not for the BC, but for another shot at quality control - there are many defects that show up under pointing (e.g. cracked/folded meplats, light cores, large changes in ogives). Visual inpection, measuring and weighing each bullet will locate the defects ... but you have to be reasonable on time contraints and choose your poison. Pointing helps me to find the outliers, the '1 in 1000' that shouldn't be there.
 
There is a difference in bullet BC and consistency when you point, or trim and point.
If you point only; you reduce the meplat size of all bullets and reduce the variation of the metplat for bullets which reduces vertical at longer ranges
If you trim and point you make the bullets more consistent while improving vertical at distance
I use a hybrid method.
I sort all bullets by OAL by .001 difference
The tailing bell curve get trimmed to the length of the MEAN. avg. i am not going to trim all bullets as this will lose approx 2% of the BC. i am only trimming the latter part of the bell curve to reduce the longer bullets back to the avg BC.

Example i recently sorted 1,200 Berger 200's the avg OAL was 1.488 anything longer I trimmed using a hoover trimmer.
The Hoover is designed to use the Ojive as it reference line. When trimming bullets the OAL is reduced to the specific Ojive and your new OAL it will be much closer to the avg. Once trimmed i am left with a much larger avg size if i want additional sorting.
Using a Hoover pointer with the specific insert i point based on OAL longest first.
 
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