real world bullet pointing data??

[AusFclass]

hi guys!

now ive had a chance to get back to the range more often ive been thinking about ordering some dies and medplat trimming and pointing bullets . id be interested to know some real world data on how much it alters your elevation settings and then i could re calculate the BC and i can let you know what i find out.

from what ive read it realy depends on the bullet you start with and how large the medplat is to begin with. i mainly shoot 6.5 and 7mm so i would mostly be interested in data for 6.5mm 130gr berger/ 7mm 180gr berger VLD and 7mm 180gr berger hybrid.

so what ill need is:

CALIBER / BULLET TYPE / WEIGHT

ACCURATE VELOCITY

THE DIFFERENCE (in MOA) BETWEEN ONE SHORT KNOWN RANGE ZERO ie 100-300yds ONE LONG KNOWN RANGE ZERO ie 700-1000yds


TRIMMED AND POINTED OR JUST POINTED?

WHAT DIE? WIDDEN OR HOOVER?

so should look something like this

* .284 win berger 180gr hybrid
* 2900fps
* 100yd- 800yd 16.12moa elevation
* trimed and pointed
* widden die

as with all data if its garbage in it will be garbage out so if you want me to give you an accurate BC of your actual bullets then it needs to be proven accurate data.

 

[makuchi]

SIR: I shoot 7mm [284 Win] at 1000 yds.....Bullet pointing is a 1% issue derived statistically. My goal is to shoot at 1/4moa...A 1moa accuracy at 1000 yds is equal to 10 inches. Bullet pointing can improve this result statistically by 1% of 10 inches. If your looking to bullet pointing alone [and I admit it's a personal examination] bullet BC variance becomes a 1% issue and wind and mirage can easily offer as much as 20% or more....If 1% will improve your shooting then please proceed....I have used the hoover pointing system and find it is very acceptable....But I have moved to other forms of time consumption that offer far better returns as much as 6% statistically.....Good luck and good shooting....BE WELL!.....V/r mk

 

[XTR]

I shoot F-TR at 1000 yds for 90% or more of my shooting.

I haven't had the opportunity to shoot side by side pointed and un-pointed, I've had plans to do so on a couple of occasions but it's just not happened. I'll probably get it done this "off season" when things slow down after next month. In talking with and reading the comments of some other shooters who have tested the biggest improvement at 1000 yards seems to be an improvement in vertical grouping.

I shoot a 30 cal and the info I've gotten from folks who have tested them is that the POI between pointed and un-pointed is almost um-noticeable. Pointing just doesn't buy you much BC on a 30cal, but it makes it more consistent so the vertical grouping is tighter pointed. Take that for what it's worth, and at 1000 yards I'm not sure how many rounds you'd have to put on target to get a statistically valid sampling. Personally, I point with a Widden die. I can point a box of 100 in about 1/2 an hours so it adds very little to my reloading time and gives me a little more confidence that I'll hit where I aim, at least in the up and down plane.

 

[AusFclass]

SIR: I shoot 7mm [284 Win] at 1000 yds.....Bullet pointing is a 1% issue derived statistically. My goal is to shoot at 1/4moa...A 1moa accuracy at 1000 yds is equal to 10 inches. Bullet pointing can improve this result statistically by 1% of 10 inches. If your looking to bullet pointing alone [and I admit it's a personal examination] bullet BC variance becomes a 1% issue and wind and mirage can easily offer as much as 20% or more....If 1% will improve your shooting then please proceed....I have used the hoover pointing system and find it is very acceptable....But I have moved to other forms of time consumption that offer far better returns as much as 6% statistically.....Good luck and good shooting....BE WELL!.....V/r mk

im not looking to use the data to put together statistical predictions more so calculate actual BC . as a statistic its a bit like trying to compare shooting a berger VLD against a berger hybrid and how much improvement you would have in using the hybrid.

another way of calculating it would be if you shot 5 shots of the un pointed and 5 of thru pointed at long ranges and using the velocity i could work it out.

i already shoot a BAT, nightforce, krieger, broughton combination so have a ffairly good platform to see if it gives any benefit but all that being said its more about giving it a go rather than winning trophies. i just like shooting accurately rifles at long range. . . and the more accurate the better :-D

 

[AusFclass]

ps sorry about the grammar!! typing off my ph is a PITA!

 

[Laurie]

Here's what I wrote in December 2010 for the January 2011 issue of Target Shooter Online magazine re a none too scientific test comparing unpointed and pointed Berger 90gn VLDs at around 2,900 fps MV and fired on the GB / British Commonwealth version of the modified international Palma / F Class target.

Note that the bullets were pointed with the original Whidden die insert just before the Bryan Litz designed much improved VLD version was introduced.


Range-Test
I can imagine many of you are thinking this is nothing but theoretical BS that won’t stand up when put to the test in real-life shooting, so Vince Bottomley and I did a little test at the end of a PSSA 900yd F-Class competition last October to see how it works out in practice. I loaded a few extra .223 rounds with 90gn VLDs out of the box, and four examples that had been pointed using a Whidden die in original form. This has a non-optimum ‘insert’ fitted and is expected to produce four or five percent BC improvement to these bullets. After we’d taken our competition shots, I fired three rounds of non-pointed ammo followed by four with treated bullets with Vince plotting them. The shots were taken as fast as the target was marked to minimise the effect of wind changes, and no wind allowance was made, a central aim used throughout.

Bryan Litz calculates the Berger 0.224” 90gn VLD has an average G7 BC of 0.281, that becoming 0.295 if a full 5% improvement were obtained through pointing. Looking at my plot for the competition, the corrected scope windage needed for the last five shots had varied from 2¾ to 3¼-MOA, this rising over the sequence. The scope setting for the last shot which was retained for the pointed bullet test was 3-MOA right windage applied. Using the Berger Bullets’ ballistics program, 3¼-MOA with this bullet at 2,900 fps MV and at 900yd equates to a 5.4mph 90° angle wind, and if this stayed constant throughout the test (unlikely given Diggle’s varying conditions), we could expect shots 1 to 3 with the unmodified bullets to strike a bit left. Running the program for the bullet at its ‘standard BC’ of 0.281 and then with the estimated improved value of 0.295, the four pointed bullets should group almost exactly six inches (0.64-MOA) higher than the first three, and two inches (0.21-MOA) to the right of them.

Vince’s plot is shown as Figure 1 with the pointed-bullet shots circled. To my surprise, all four struck higher than their unpointed brethren, two of them markedly so, up a full MOA. (I had expected a degree of overlap between the two groups.) The group centre for the pointed quartet is around three-quarters MOA higher on the target. It’s more difficult to see what effect there was on windage. Shots 1 and 3 with the unmodified bullets are to the left of the centreline as expected, but shot number 2 is nearly half-MOA to the right suggesting a wind drop when that shot was taken. It is also higher than the other two, possibly due to there being a vertical wind-component, as is often encountered at Diggle. Shot number 4 is in line with the unmodified bullets and is the lowest of the pointed bullets, so there may have been a gust here that also blew the bullet down a bit. The other three are grouped closely in wind terms and are a quarter to third-MOA to the right of the target centreline. Short of having somebody do a wind call throughout the shoot, we really can’t say how much of this movement is down to wind changes and how much due to BC improvement from the pointing, but it looks like some benefit has been obtained in line with the prediction, maybe even a bit more.



As noted, the potential % BC improvement depends on the combination of the original meplat diameter and the calibre with small calibre bullets being improved correspondingly more than large. Nevertheless, the 0.7 to 0.8-MOA group centre rise at 900yd was more impressive than I was expecting. I now work on an assumed 5% BC improvement in 90s in .223 Rem and 3% for.30-calibre VLDs and Hybrids in .308 Win through pointing with John Whidden's improved 'VLD insert'. Some people have noticed elevation consistency improvements through pointing, but the two ranges I shoot most of my long-range comps on Diggle in Northern England and Blair Atholl in Scotland lie in angled valleys and are notorious for seeing an elevation component often accompany a wind strength or angle induced windage change.

 

[Keith Glasscock]

I recently ran a test with my 308 at 1k yards. Launch velocity was 2595 with a 200 grain Berger hybrid. The pointed bullets impacted ~5" higher on the target (two groups of 5)

If you look up bullet pointing on benchrest central, Dave Tooley did some testing a couple of years ago using a doppler radar. His results and mine vary in the BC by .001 (G7). Considering hte potential noise in the data, we are basically of the same opinion: Pointing adds ~3% to the G7 BC on a 30 cal bullet.

Hope this helps,
Keith

 

[sdeal5]

Not very scientific, but on 3 different occasions I have compared trimmed and pointed ( Hoover equipment) versus unaltered bullets @ 1000 yds. ---Berg. .284, 180 gr. hybrids @ 2960. 7-8 mph wind from 7:30 ( prevalent condition on this range). All 3 times, the pointed bullets averaged 1moa higher and were 1/2 moa inside the unaltered bullets. These were 5 shot grps on 2 occasions, and the last time they were 10 shot grps. Had a couple of overlaps each time on windage when I missed a let-off but the center of the grps were about 5" apart. Vertically the pointed bullets were consistently 10" higher with a somewhat tighter vert. spread. For no longer than it takes to trim and point a box of bullets ( less than an hour, even with set-up) I feel it is worth it. If my simple pea-brain thinks it helps, it IS helping! Hoover Acc. One trimmer and pointer are quality products, and easy to use. I'm sure Mr. Whidden's are equally as good. I doubt this info will help anyone in computing a BC, I just know what I've seen on the targets.-----Scott

 

[AusFclass]

Not very scientific, but on 3 different occasions I have compared trimmed and pointed ( Hoover equipment) versus unaltered bullets @ 1000 yds. ---Berg. .284, 180 gr. hybrids @ 2960. 7-8 mph wind from 7:30 ( prevalent condition on this range). All 3 times, the pointed bullets averaged 1moa higher and were 1/2 moa inside the unaltered bullets. These were 5 shot grps on 2 occasions, and the last time they were 10 shot grps. Had a couple of overlaps each time on windage when I missed a let-off but the center of the grps were about 5" apart. Vertically the pointed bullets were consistently 10" higher with a somewhat tighter vert. spread. For no longer than it takes to trim and point a box of bullets ( less than an hour, even with set-up) I feel it is worth it. If my simple pea-brain thinks it helps, it IS helping! Hoover Acc. One trimmer and pointer are quality products, and easy to use. I'm sure Mr. Whidden's are equally as good. I doubt this info will help anyone in computing a BC, I just know what I've seen on the targets.-----Scott

from what i can figure thatd give you a .375 bc but youd have to cross reference it against any other zeros at known distances.

 

[AusFclass]

I recently ran a test with my 308 at 1k yards. Launch velocity was 2595 with a 200 grain Berger hybrid. The pointed bullets impacted ~5" higher on the target (two groups of 5)

If you look up bullet pointing on benchrest central, Dave Tooley did some testing a couple of years ago using a doppler radar. His results and mine vary in the BC by .001 (G7). Considering hte potential noise in the data, we are basically of the same opinion: Pointing adds ~3% to the G7 BC on a 30 cal bullet.

Hope this helps,
Keith

i think ur BC should be around .338 but as above it would be interesting to use that figure to print off a drop chart and see how it compares to your other recorded zeros down the range

 

[Laurie]

i think ur BC should be around .338 but as above it would be interesting to use that figure to print off a drop chart and see how it compares to your other recorded zeros down the range

The ONLY reliable way to run comparisons in such a case is shooting the lots side by side in as steady conditions as possible in one session using one scope setting throughout

Run any good ballistics program and you can see that changes in atmospheric pressure, air temperature, humidity etc can easily change long-range strikes by a full MOA. Ground conditions / features can see wind add vertical components, not to mention the effects of tail and headwinds. These factors can all easily add up to a greater effect than the relatively small benefits of pointing. My records for F Class matches shooting ballistically efficient .308 Win loads in F/TR show 1,000yd elevation settings vary noticeably between different rifle ranges, as expected, but can also vary significantly on different outings on individual ranges as a result of weather conditions on the day.

The evidence from a number of sources and users is that pointing makes a small improvement to most makes of match bullet, which is what John Whidden and Hoover claim. In some older batches from some makes which see marked tip length variations and a lack of symmetry around the meplat - getting rare nowadays - trimming before pointing would almost certainly improve consistency too.

I'm gratified that my unscientific guesstimate of a 3% improvement in 30s ties in with Keith's and Dave Tooley's results. I still reckon 5% is about right for heavy 0.224s, and would split the difference for 6mm, 6.5mm, and 7mm bullets.

 

[memilanuk]

Some of that data that Keith (Busdriver) alluded to...

...some preliminary numbers from the Doppler radar test.

Average G7 BC from 500-1200 yds.

Stock .289

Trimmed .286

Pointed .298

Trimmed and pointed .297

Bullets used were 210 VLDs, pointed by me using a Whidden die and meplat uniformed using my Giraud trimmer and the appropriate accessories. Bullets were fired from a magnum of some sort (I wasn't present for the actual shooting exercise).

 

[XTR]

Run any good ballistics program and you can see that changes in atmospheric pressure, air temperature, humidity etc can easily change long-range strikes by a full MOA. Ground conditions / features can see wind add vertical components, not to mention the effects of tail and headwinds. These factors can all easily add up to a greater effect than the relatively small benefits of pointing.

Laurie, Density altitude is one of the factors that I rarely see square range competition shooters understand, or care about because we get lots of sighters. The 'tactical" crowd who tend to get one shot on target at unknown distances have to take it to heart. I've seen my vertical change by a full MOA between an 0900 relay when the temperature is in the 70s (F) and one after noon when it's in the mid to upper 90s (F). I occasionally pull out my Kestrel and look at the DA. Our range in Oak Ridge sits at an altitude of about 925, I've seen the DA vary from -200 to as much as +4500 on different days.

I also think this plays into some of the unrealistic MVs reported on the interweb. When you see someone post that he's driving 175s from a 24" barrel at 2700FPS+ he's probably not giving reliable chrono data but using his come ups and running the numbers in JBM till he gets a MV that works but not taking DA into acct.

Yes, I point, does it help much, probably not a whole lot, but if it gets me that .25 inches closer to the X and gets me a 10 touching the line then it's worth it, and it doesn't cost much in time or money.

 

[Laurie]

I also think this plays into some of the unrealistic MVs reported on the interweb. When you see someone post that he's driving 175s from a 24" barrel at 2700FPS+ he's probably not giving reliable chrono data but using his come ups and running the numbers in JBM till he gets a MV that works but not taking DA into acct.

Yes, those are BIG changes! Another factor that sees so many dubious MV guesstimates kicked around is scope adjuster (in)accuracy. Very few people run a test to see what a 30-MOA elevation change on the turrets actually does on paper. A friend who has tested maybe 20 target scopes in recent years for magazine reviews has found 4-8% errors in adjustments at 100yd very common, even on expensive target models. They have got a lot better in recent years though. (He uses a 6PPC bench gun, so the effect of group dispersion is minimised.)

Yes, I point, does it help much, probably not a whole lot, but if it gets me that .25 inches closer to the X and gets me a 10 touching the line then it's worth it, and it doesn't cost much in time or money.

Yes, me too. Any little benefit helps - and I need it! It's as much psychological as actual too, I reckon - having as good quality ammunition as you can produce and having faith in it. Walking around the firing lines and looking at people's open ammunition boxes (we don't worry that much about radiated heat here in the UK, and this year the ammo in open boxes is more likely to be cooled than heated, we've had such a miserable summer!), it's obvious that many long-range 'Effers' point.

 

[Keith Glasscock]

i think ur BC should be around .338 but as above it would be interesting to use that figure to print off a drop chart and see how it compares to your other recorded zeros down the range

I am more of the opinion that the bullet (assumed out of the box G7 BC of .320) is running .328 with pointing.

I have run the drop chart for 600, 800, 900, and 1000 and the predictions line up well, within reason.

What I have learned is that the BC increase really doesn't mean a whole lot. Any advantage gained in less drift (in these small increments) is offset by lack of good return data from POI of the prior shots. What I mean is that you cannot resolve the difference in POI of .24" (the 1 mph difference in drift between pointed and unpointed), but that big of a wind call error would put both shots solidly in the 9 ring. Thus, you cannot "see" the difference in windage from long range, and even if you could, the likelyhood of actually being able to point to it as the cause of a gained point would be minimal because none of us can consistently hold even 1" at 1k, much less 1/2".

My experience shows me that I can pick up one point out of every 25 shots in switchy conditions by using a bullet with a 35% increase in BC and a wind deflection decrease of ~2.5" per mph. Where I tend to pick up points more rapidly is during chaotic weather conditions when it is nearly impossible to tell which direction the wind is blowing at any given moment. In more stable conditions, I really have to work hard to keep up with the better shooters.

The one thing that pointing (and trimming) can do for me is improve shot-to-shot BC consistency. That is what I need to be truly competetive.

 

[AusFclass]

i think ur BC should be around .338 but as above it would be interesting to use that figure to print off a drop chart and see how it compares to your other recorded zeros down the range

I am more of the opinion that the bullet (assumed out of the box G7 BC of .320) is running .328 with pointing.

I have run the drop chart for 600, 800, 900, and 1000 and the predictions line up well, within reason.

What I have learned is that the BC increase really doesn't mean a whole lot. Any advantage gained in less drift (in these small increments) is offset by lack of good return data from POI of the prior shots. What I mean is that you cannot resolve the difference in POI of .24" (the 1 mph difference in drift between pointed and unpointed), but that big of a wind call error would put both shots solidly in the 9 ring. Thus, you cannot "see" the difference in windage from long range, and even if you could, the likelyhood of actually being able to point to it as the cause of a gained point would be minimal because none of us can consistently hold even 1" at 1k, much less 1/2".

My experience shows me that I can pick up one point out of every 25 shots in switchy conditions by using a bullet with a 35% increase in BC and a wind deflection decrease of ~2.5" per mph. Where I tend to pick up points more rapidly is during chaotic weather conditions when it is nearly impossible to tell which direction the wind is blowing at any given moment. In more stable conditions, I really have to work hard to keep up with the better shooters.

The one thing that pointing (and trimming) can do for me is improve shot-to-shot BC consistency. That is what I need to be truly competetive.

using several zeros and back calculating like you have done is really the best way of determining how much pointing alters BC. with VERY accurate data including altitude and humidity etc etc it could be done with a smaller sample but the equipment needed is out of my reach and thats why its good to bounce some ideas around.

 

[Leaddog]

I like what Laurie said.... 'Some people see elevation consistency improvements'. That's me.

I trim and point using the Whidden System. Lately, I have gone to just pointing and see the same results downrange as if I trimmed and pointed. I usually shoot 600 yards with the Berger 185LRBT's and see a solid 1/2 minute elevation advantage over the sorted out of the box bullets. Perhaps I'll see a trim v. trim and point difference at 1000, but I don't have enough data with my equipment to make that call yet.