265 gr AT RBBT, expansion, penetration and weight retention test results....

Fiftydriver

Official LRH Sponsor
Joined
Jun 12, 2004
Messages
7,566
Location
Fort Shaw, Montana
TO all,

I was able to get out this morning and do my best to get some testing done with these bullets. I wanted to test penetration, expansion and weight retention of these new bullet designs in preperation for my upcoming elk hunt.

First up was the expansion and weight retention tests. To do so, I go to a shooting area that has a clean hill side of very pure clay. The stuff is actually pretty neat. Right now its hard as a rock because its dry so I took and dumped 10 gallons of water in one area to really soften it up. Let it set for 20 minutes or so to soak in well and then drove back to my shooting location.

I also wanted to check my drop numbers so I set up at 440 yards which is dead zero using my first mil dot down from center on my Weaver Tactical FFP scope. I had set up a target just in front of the flat face of the hill so I could check accuracy, drop and also get the bullets after ward. I shot a total of five shots and then walked back to see what the bullets looked like.

I recovered 4 of the 5 fired bullets. Not sure where the one went but I could not find it for the life of me and I was getting tired of digging around in the clay mud looking for it!!!!

All bullets expanded very nicely with an average diameter of 0.557" with the smallest diameter being 0.431" and the largest being 0.688". All bullets retained their jackets and all had a decent amount of lead retained in the jacket as well.

Two of the bullets actually had the aluminum tipped still in the expanded bullet.

Retained weight was as follows for the four bullets recovered:

141 gr (53.2%)
218 gr (82.3%)
174 gr (65.7%)
187 gr (70.6%)

Average retained weight was 180 grains for an average of 68 % weight retention. I was, to be honest very impressed by this and was expecting the retained weights to be well below 50%. This is actually not all that far off what an Accubond will get you.

Now this impact media is very dense, in an animal or fluid, expansion will obviously be different.

By the way, accuracy at 440 yards was below 1/2 moa for all shots and drop was very close to right on the money where it should be. I was about 1 moa to the right however so I wanted to correct for that.

To test penetration, I wanted more of a test on the bullet then just water filled jugs. As such, I took one of my old Brownells catalogs and one of my very thick JLindustrial catalogs. I set up a 2.5 gallon water jug up first, then the 3" thick JL catalog, another 2.5 gallon water jug, the second book and finally a 1 gallon milk jug full of water.

I had to set the targets up on a flat surface and the best one was roughly 395 yards from my shooting position. Unfortunately there was no solid backstop. THe total length of the jugs and book line was roughly 26" front to back.

At the shot, the row of target jugs and books simply rolled every direction and wet paper flew all over.

I drove over and was again suprised at what I saw. First jug has a perfect bullet hole, impacting a bit high of vertical center and on the left side of the jug. Gave her more to the left then needed. Back side of jug was severely damaged with a 5" ragged hole torn in the heavy jug.

exitfirstwaterjugkg1.jpg


You can see the impact hole on the back side of the tear.

impactfirstbooktw8.jpg


This pic shows the impact on the first book. You can see by the bullet hole that the aluminum tip has either begun to come off the bullet or the bullet is beginning to tumble. I believe the aluminun tip is coming off here because the expanded larger bullet hole at the base of the tip cut is pretty round, not like the entire bullet is tumbling.

exitfirstbookvs8.jpg


Here is a picture of the exit hole on the first book. You can see that there is a well defined round wound channel through the book, again telling me that the bullet has not tumbled.

secondwaterjugsu2.jpg


THis is a pic of the entrace of the second water jug that was positioned behind the first book. expansion is dramatic and I am not sure that the jug was not ruptured by the compression of the book against it before the bullet impacted because there is very little sign of an exit hole by the bullet itself other then the rupture all around the jug.

You can also see on the handle of the jug that the aluminum tip has flown clear of the expanding bullet and in the case of big game hunting will only add to the vital tissue distruction.

impactsecondbookmb2.jpg


This is a pic of the entrace hole on the second book. THis is after impacting and penetrating the first 2.5 gallon jug, first 3" thick book, second 2.5 gallon water jug and finally impacting the second book. Here we see either the first signs of the bullet tumbling or expasion is getting to the point that the bullet diameter has increased significantly. You will also notice above the main bullet hole that the bullet aluminum nose is still traveling along with the main bullet body impacting roughly 2" high and 2" to the left of the main bullet penetration path. Interestingly enough, the tip was recovered around page 230 of the brownells catalog so it still penetrated more then half the width of the second book.

exitsecondbookwn0.jpg


This is the exit hole of the second book. It appears that the bullet may either be laying on its side or again, it has reached full expansion and that is the reason for the oblong hole. Clearly, the majority of the bullet is still in tact and it still has plenty of energy to easily punch though this second book.

The final 1 gallon water jug was barely cut on the top of it by the passing bullet, just enough to say it was hit and that was about it. It did however hit it hard enough to roll it 2 feet to the right of where it was sitting at the shot.

Unfortunately there was no solid back top behind the line up, only a shallow angled hillside going up into a larger hillside. I could see where the ground had obviously been torn up by the bullet impact but there was no sign of the bullet as I believe it hit the hard ground at the angle and rolled up into the steeper part of the hill backstop and I could not find any sign of it.

This is only one bullet but obviously it has enough integrity to penetrate 26 inches of water jugs and heavy books and still have enough zip to carry it to god knows where after hitting the hill behind the target.

Again, I will be honest, I was surpised at this. I was expecting to find the bullet possibly in the first book, but more likely between the first and second book. I would have never guessed it would completely penetrate the line.......

I also do not mind the fact that the aluminum tip cleared the bullet. Only adds to the distruction this bullet will inflict at long range.

Now this test was not really long range but if the bullet is performing here and showing obvious energy transfer with good penetration as well, it should only get better at long range where expansion may not be as severe. More testing to come with this bullet but for the time being, until my hunt next week, I feel much better pointing this bullet at a bull elk.

I will still intentionally avoid a shoulder bone at all cost just in case there is a problem but I suspect, after seeing this penetration and bullet weight retention, the bullet will perform even better terminally then I first imagined.

Then its onto testing the bullet in my 338 AM for the upcoming pronghorn season starting Oct 7th!!! Looking to break the 1000 yard barrier on a big buck pronghorn with the lightweight 338 AM, possibly MUCH farther then that if the conditions are right for it.

Kirby Allen(50)
 
Very good pics! They speak volumes.

Just a few questions:

Impact velocity was how fast?
Do you have pics of the bullets fired into the clay?
Cost and availability of these bullets as of today?
 
GG,

Yes I will get them tomorrow. I was going to get them posted today but some customers showed up and got me doing other things(work!!).

The clay is pretty dense and as such, the bullets expand significantly, in fact most of them are expanded pretty much to nearly the beginning of the RBBT. THis did not suprise me as they were stopped cold in only 5 to 6" of penetrating the clay, dense stuff.

Still I Was suprised that they retained as much weight as they did. Obviously these are only 4 test bullets but for those four, I was impressed with the weight retention.

Velocity wise, I have been getting a bit better idea of BC for these bullets. Seems to be running in the .9 range. I did not set up a chrono at 440 yards simply because I have not learned the exact consistany of the load to that point and my drop numbers were not yet proven well enough to set up a chrono.

My estimate of impact velocity would be right around 2500 fps +/- 50 fps.

Cost right now has not been offered by Richard. I asked him a couple times and he said we need to prove they are worth selling first so right now that is up in the air.

For what you get, I would say anything from 70 to 85 cents a piece would be realistic to pay for these bullets, hell the hornady 750 gr A-Max is getting over $2 each and if you go by the cost of lead these days, the ratio cost for a 265 gr Aluminum tip on that price scale would be 71 cents each.

To answer your question, I do not know yet but I would suspect in that range. ALOT cheaper then a LRB bullet!!!

I will try to get pics of the expanded bullets tomorrow and post them.

Kirby Allen(50)
 
Looks like it will work on your Elk hunt....It will be interesting to see the results out of the 338 AM at 3500 fps!!!! I would imagine that close range, they would be very destructive:D:D:D

I would like to test the 7mm bullets now when they become available.
 
Looking to break the 1000 yard barrier on a big buck pronghorn with the lightweight 338 AM, possibly MUCH farther then that if the conditions are right for it.

Good luck on getting good conditions.
 
Went out this morning with my Dad for an early morning drop chart test with the lightweight 338 AX.

Drove to our shooting spot, had dad spot a nice target rock, roughly 5" in diameter. He guided me onto the rock and then he ranged it. 800, 801, 800 yards was the called range. Plugged everything into my palm using the current conditions and with a 0.920 BC.

Results listed a hold of 3.5 mils for a dead on hold at 800 yards. Found the rock, settled in and placed the rock between the third and fourth mil dot down from the main crosshair. Tripped the trigger and the bullet was there before I recovered from recoil. All I could tell was there was a good dust cloud that rose up right around the target rock.

Dad reported horizontal center, vertical +4" which ment the bullet landed 4" high of the center of the rock, right on the top end of the rock.

Raked in a second round, again at the trigger break the rifle rolled enough to prevent me from seeing the impact.

Dads report this time was 3" left, horizontal, vertical center. Meaning the bullet landed on the left edge of the rock.

Stroked the bolt stripping the third and final round out of the mag box, trigger broke and dust flew.

Dads report, same exact impact and shot #1.

All three shots landed within 5" of each other CTC. All shots landed within 4" or less of point of aim at 800 yards.

Put the rifle in the case and headed home. The rifle will not be fondled again until we are after old wapiti!!!! She is ready. Confirmed ranges at 100, 300, 450 and 800, drop chart is now matching up perfectly it seems.

Week from today things will be exciting hopefully!!!

Stay tuned.

Kirby Allen(50)
 
Warning! This thread is more than 18 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Recent Posts

Top