The little dot left on bell target surrounds

[trajectory]

I try to get my pellets through the little hole in the middle of the target so that I don't mess up the paint.

Yes, but think of all the trouble someone went to making those scoring rings, seems rude not to use them occasionally.

[Solvo]

I've observed it at various ranges with rifles around 11.5ft/lb but sadly I don't have the ability to run tests for this myself. None of my rifles are adjustable and they're either tuned to between 10 & 11.5 or wheezing antiquities that either strike with such a weak force you can reuse the pellet - or simply cant reach a target

Interesting point about the flat heads though. Pure conjecture here but I wonder if the lack of a pip with those is simply that there isn't an small impact point carrying the initial energy transfer. Without that initial point to deflect around there may be enough sideways movement with the impact to dislodge the cone with the rest of the lead.

I'll have to have a rummage through the spent rounds i have and see if i can match any up.

[trajectory]

I've observed it at various ranges with rifles around 11.5ft/lb but sadly I don't have the ability to run tests for this myself. None of my rifles are adjustable and they're either tuned to between 10 & 11.5 or wheezing antiquities that either strike with such a weak force you can reuse the pellet - or simply cant reach a target

Interesting point about the flat heads though. Pure conjecture here but I wonder if the lack of a pip with those is simply that there isn't an small impact point carrying the initial energy transfer. Without that initial point to deflect around there may be enough sideways movement with the impact to dislodge the cone with the rest of the lead.

I'll have to have a rummage through the spent rounds i have and see if i can match any up.

Slightly similar position here with the inability to conduct tests at varying velocities; although I do have a couple of pistols which might provide some results at around 290-310fps.

Your speculation about the wadcutter style might be correct. The RN pellet with its smaller leading initial contact area would have a different energy transfer profile compared to the wadcutter with an almost instantaneous total surface area contact. Might be enough to explain the difference between the two. You may have something there.....

[Solvo]

Dug up some old rounds for anyone still interesting in the effect.
Don't ask me why i have over a kilo of pellet scrap, I guess even 20 years ago it was interesting to me.

I used to know what all these were but it's been years since i spent any time studying them.

All of these ones are .177

I think top left is a AA Field
Bottom Left is almost certainly an RSW Super-H-Point
The fine concentric rings visible on these two are the inside of the skirt, which bears those same fine rings on a whole pellet.
Each of these was recovered from a spinner or knockdown, the energy imparted to the moving plate prevent the formation of the pip, it's still there metallically but buried under the skirt which has not yet peeled away as the force was transferred to the plate.

The three near perfect rounds are an RWS Geco (Fired from a Diana 16 into paper pinned to straw), Unknown (possibly a geco) and a Bisley Magnum I think, latter two were recovered from a water test.

Bottom right is one of the cast off splash rings i referred to, the micro impact paper from MIT I linked refers to this effect as 'Jetting'

The top right are four of the pips we're discussing, you can also clearly see the outer rings (dark grey on the left most three and a thin line on the far right one) which are the tail ends of the pellet skirt where it finally caught up with the head and having spend all its energy stopped there.
I think the one on the far right is also an AA Field (I didn't have many pale alloy pellets back when these were fired), based on the other rounds i used back then the remaining three are most likely RSW SuperDome



Not sure there's too much interest in the terminal ballistics of lead pellets on steel targets. Pretty much all the research in articles in AG/AGW always focus on ... less solid targets.

[HW777]

1 million FPS slow motion video of bullet impacts made by Werner Mehl from Kurreit

On Youtube is worth a watch, it also contains some pellet impacts

[Scott.]

I try to get my pellets through the little hole in the middle of the target so that I don't mess up the paint.

Thank god for you Mick, I thought I was doing it wrong by missing the paint

[keith66]

Exactly the same principles apply to large meterorite craters & the rebound leaves a pip in the middle of those too!

[trajectory]

I hadn't ever given terminal ballistics of pellets against solid backstops much thought other than ensuring the backstop was both safe & reliable but it's been interesting reading the replies & having a look at what else is around on the subject. The videos were worth a look & I never realised that craters exhibited the same central pip.....

[edbear2]

Very interesting replies, from everyone.
In the past I have seen the 'pipping' with domed pellets & learnt that they were used in bell target shooting for this reason as other styles don't produce the same effect. I had also noticed that some domed pellets fired perpendicularly to a flat steel surface have a tendency to almost turn themselves inside out & moderate velocity pellets thus fired often display a central pip on the non impacting surface although the impact surface appears pretty uniformly flat. Not sure what the implications of that are but on reading Solvos excellent terminal ballistics explanation it made me wonder if / what the minimum / maximum velocity of a RN pellet might be if it were to produce a pip on a bell target. Bell target rifles have to be below 6 ft/lb, so does a very low sub 6ft/lb velocity produce the same effect? Conversely is there a maximum velocity beyond which the phenomena ceases to be (way above 6ft/lb?)
I think I need to have a plink at some paint....

Only in some leagues. we use full power TX's and Hw's and use the "pip" to deternine the score when on a line.

Random link to one of our league teams who have found some old records;

https://drive.google.com/file/d/0B6H...owRk5Od0k/view

ATB, Ed

[frogboy]

Only in some leagues. we use full power TX's and Hw's and use the "pip" to deternine the score when on a line.

Random link to one of our league teams who have found some old records;

https://drive.google.com/file/d/0B6H...owRk5Od0k/view

ATB, Ed

Oh for Christ’s sake Ed, Astley still winning the league even back then.
Couldn’t you just show a record of when we once won something and have done with that?