First I want to thank Mid Tompkins for doing so much to make this test possible. Without him it would not have happened. Also I want to thank Sherri Hurd and Michelle Gallagher for their part in putting 950 shots down range using a 6.5X284 in a little over 6 hours. You both earned those sore shoulders.
On January 3rd at Ben Avery Shooting Facility in Phoenix, AZ we,in my opinion) solved the bullet failure issue. We conducted a test during which 220 Berger 6.5mm 140 gr VLD made with regular J4 jackets were fired in two different barrels. After these rounds were fired we shot another 220 rounds of Berger 6.5mm 140 gr VLD made with thicker J4 jackets. The results were interesting to say the least.
Two barrels that had been provided by Krieger were chambered by Mid Tompkins. These barrels were put on two F-Class rifles,Mid's and Bob Mead's). A front rest, rear bag and shooting mat were used in shooting these rifles F-Class style.
Mid and Michelle spent much of the holidays loading the 950 rounds shot during this test. The ammo was loaded in Lapua cases with 49.5 gr of H4350.
Present during the test were Mid Tompkins, Michelle Gallagher, Sherri Hurd, Jeremy Hurd, Bob Jones, Alan Elliot, Walt Berger and I. We made sure that for each shot there were at least two people watching through spotting scopes. All shots were documented.
The goal was to shoot all the rounds in highly abusive conditions and then observe if the bullets would fail. We did not alter the barrels or the load in an attempt to create failures on purpose. These barrels and loads were in every way in the same condition when we started as any combination would be on match day.
The procedure used for this test was to fire 20 rounds with one rifle then quickly switch to the other rifle. We would shoot all 220,in each barrel) of the regular jacket bullets first then shoot all 220 of the thicker jackets. This course of fire was meant to duplicate match type strings and the rapid firing was to produce the harshest conditions possible for the bullets.
As you can imagine the barrels were very hot to the touch once we got through the first few strings of 20 shots. They would remain hot for the rest of the day.
We started with the .257 barrel first. We were not testing barrels so observations made about the barrels are secondary to the focus of the test. I mention this because I predicted that the .257 bore diameter would produce fewer failures since it was larger than the .256 bore diameter. I was proven wrong.
The .257 bore diameter barrel produced the first bullet failure at shot 106. The .256 bore diameter barrel produced its first bullet failure at shot 151. Even more interesting was the fact that the .257 barrel produced a total of 27 failures,with regular jacket bullets) right up to the last shot. The .256 barrel produced only 12 failures and stopped producing failures when the barrel was cleaned after shot 180. 40 shots were fired after both barrels were cleaned.
Now for the good news. After we finished shooting the bullets made with regular jackets we switched to the thicker jackets. Again both barrels shot 220 each by shooting a string of 20 and then switching to the other rifle. ALL 220 BULLETS MADE WITH THICKER J4 JACKETS,IN BOTH BARRELS) MADE IT TO THE IMPACT BERM.
So that we did not destroy one of Mid's target frames the scopes were adjusted so that we could aim on a target but the bullets would hit the impact area of the next target. At the beginning of the thick jacket shooting we did shoot one 10 shot string on the target. The results were a 12 oclock 6 due to scope adjustment, 8-Xs and 1-10,string shot by Michelle G.) Accuracy was not the focus of this test but it looked good for ten shots,once we got the scope adjusted).
To verify that something had not changed in the barrel for the thicker bullets we shot another 20 bullets made on the regular jackets in the .257 barrel after the thicker jacket shooting was completed. 9 out of 20 shots fired did not make it to the berm.
Another interesting result was that while we were shooting the thicker jacketed bullets both barrels produced several blown primers. The .257 barrel produced 14 blown primers and the .256 barrel produced 5. There were no blown primers while shooting the regular jacket bullets. We did chronograph five shots using regular bullets at a MV range of 2,996 to 3,024 fps. The chronograph was not working later in the day so we could not check the MV produced when shooting the thicker jacket bullets.
We continued shooting after thoroughly cleaning the .257 barrel using moly coated bullets made with regular jackets. 50 rounds were fired with 14 failures. It is my opinion that the abuse this barrel had experienced does not allow for an appropriate testing of the effectiveness of moly. These bullets were shot mostly out of curiosity. It is certainly clear that moly is not a cure all for bullet failure however I still believe that it helps reduce friction which is the cause of these bullet failures.
It is my conclusion that bullets made with thicker jackets are more capable of sustaining significantly higher levels of abuse before producing a failure. We are gong to do this same test again but this time we will use Bartlein barrels. The purpose again is not to test the barrels but to focus on the results produced by using jackets of different thicknesses.
Even though we are going to conduct another test we are already working on the production of a full line of VLD-THICK bullets in 6.5mm, 6mm, 22 cal and 7mm which will be specifically meant for target competition shooters. I will attempt to attach a detailed report of the specifics of the test.
Regards,
Eric
On January 3rd at Ben Avery Shooting Facility in Phoenix, AZ we,in my opinion) solved the bullet failure issue. We conducted a test during which 220 Berger 6.5mm 140 gr VLD made with regular J4 jackets were fired in two different barrels. After these rounds were fired we shot another 220 rounds of Berger 6.5mm 140 gr VLD made with thicker J4 jackets. The results were interesting to say the least.
Two barrels that had been provided by Krieger were chambered by Mid Tompkins. These barrels were put on two F-Class rifles,Mid's and Bob Mead's). A front rest, rear bag and shooting mat were used in shooting these rifles F-Class style.
Mid and Michelle spent much of the holidays loading the 950 rounds shot during this test. The ammo was loaded in Lapua cases with 49.5 gr of H4350.
Present during the test were Mid Tompkins, Michelle Gallagher, Sherri Hurd, Jeremy Hurd, Bob Jones, Alan Elliot, Walt Berger and I. We made sure that for each shot there were at least two people watching through spotting scopes. All shots were documented.
The goal was to shoot all the rounds in highly abusive conditions and then observe if the bullets would fail. We did not alter the barrels or the load in an attempt to create failures on purpose. These barrels and loads were in every way in the same condition when we started as any combination would be on match day.
The procedure used for this test was to fire 20 rounds with one rifle then quickly switch to the other rifle. We would shoot all 220,in each barrel) of the regular jacket bullets first then shoot all 220 of the thicker jackets. This course of fire was meant to duplicate match type strings and the rapid firing was to produce the harshest conditions possible for the bullets.
As you can imagine the barrels were very hot to the touch once we got through the first few strings of 20 shots. They would remain hot for the rest of the day.
We started with the .257 barrel first. We were not testing barrels so observations made about the barrels are secondary to the focus of the test. I mention this because I predicted that the .257 bore diameter would produce fewer failures since it was larger than the .256 bore diameter. I was proven wrong.
The .257 bore diameter barrel produced the first bullet failure at shot 106. The .256 bore diameter barrel produced its first bullet failure at shot 151. Even more interesting was the fact that the .257 barrel produced a total of 27 failures,with regular jacket bullets) right up to the last shot. The .256 barrel produced only 12 failures and stopped producing failures when the barrel was cleaned after shot 180. 40 shots were fired after both barrels were cleaned.
Now for the good news. After we finished shooting the bullets made with regular jackets we switched to the thicker jackets. Again both barrels shot 220 each by shooting a string of 20 and then switching to the other rifle. ALL 220 BULLETS MADE WITH THICKER J4 JACKETS,IN BOTH BARRELS) MADE IT TO THE IMPACT BERM.
So that we did not destroy one of Mid's target frames the scopes were adjusted so that we could aim on a target but the bullets would hit the impact area of the next target. At the beginning of the thick jacket shooting we did shoot one 10 shot string on the target. The results were a 12 oclock 6 due to scope adjustment, 8-Xs and 1-10,string shot by Michelle G.) Accuracy was not the focus of this test but it looked good for ten shots,once we got the scope adjusted).
To verify that something had not changed in the barrel for the thicker bullets we shot another 20 bullets made on the regular jackets in the .257 barrel after the thicker jacket shooting was completed. 9 out of 20 shots fired did not make it to the berm.
Another interesting result was that while we were shooting the thicker jacketed bullets both barrels produced several blown primers. The .257 barrel produced 14 blown primers and the .256 barrel produced 5. There were no blown primers while shooting the regular jacket bullets. We did chronograph five shots using regular bullets at a MV range of 2,996 to 3,024 fps. The chronograph was not working later in the day so we could not check the MV produced when shooting the thicker jacket bullets.
We continued shooting after thoroughly cleaning the .257 barrel using moly coated bullets made with regular jackets. 50 rounds were fired with 14 failures. It is my opinion that the abuse this barrel had experienced does not allow for an appropriate testing of the effectiveness of moly. These bullets were shot mostly out of curiosity. It is certainly clear that moly is not a cure all for bullet failure however I still believe that it helps reduce friction which is the cause of these bullet failures.
It is my conclusion that bullets made with thicker jackets are more capable of sustaining significantly higher levels of abuse before producing a failure. We are gong to do this same test again but this time we will use Bartlein barrels. The purpose again is not to test the barrels but to focus on the results produced by using jackets of different thicknesses.
Even though we are going to conduct another test we are already working on the production of a full line of VLD-THICK bullets in 6.5mm, 6mm, 22 cal and 7mm which will be specifically meant for target competition shooters. I will attempt to attach a detailed report of the specifics of the test.
Regards,
Eric
