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Drop in Velocity?

 
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  #1  
Old 01-20-2005, 11:50 PM
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Drop in Velocity?

Hello everyone, I am new to the Forum lots of good info on here . I was hoping to get some good advice. I got this virus called 30-378 itus ( I had to have a super gun ) 3 years ago. I knew nothing about reloading or custom guns. I did know that I wanted to be able to shoot deer as far as I coud see. In reasearching what caliber I wanted I ordered a Lazzeroni 7.82 Warbind model 2000 not the TRG-S. It has a 27 inch barrell 1-12 twist. I thought the faster the better. I read everything I could about reloading and started trying to work up a load for my new gun. My best load was 103.5 gr. IMR 7828 FED 215M primers Lazzeroni 150 gr. Coated X bullett AOL 3.575 This would shoot 3729 averaged over 50 shots with ES. of 22 FPS. It would shoot 1moa groups I thought that was great ( until I found this sight everyone here shoots 1/2 or 1/4 moa) so to get to my question I have taken deer with this rifle out to 536 yards with 1 shot kills. The other day at my farm I missed a doe at 527 yards. I did not come close she never even moved so I went to the range the next morning . I was shooting low. So I broke out the Chronograph. My shots were around 400 fps. slower, same temperature,same loads ,so I cleaned my barrell and made sure the copper fowling was out and tried again my next shots were 3261 fps and went up every shot 6 shots later I was at 3493. I think it is time for a new barrel. I have shot the gun about + or - 800 times. What do you think. Any other Ideas. If so who can I send it to to have a new barel chambered and installed in the same caliber. Also is there something about running these bullets out so fast that makes them not as accurate as other calibers. Like I said my gun shoots 1moa with every thing I try I cant get them any better even 168 match bullets shoot 1moa. Help [img]/ubbthreads/images/graemlins/confused.gif[/img]
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Old 01-21-2005, 10:05 AM
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Re: Drop in Velocity?

Bcraft1111,


Fist off, welcome to LRH. Good to have you with us [img]/ubbthreads/images/graemlins/smile.gif[/img].

Well, I am not a huge fan of the Lazzeroni rounds as a hole, on paper performance numbers are pretty impressive but unless you use his rifles and bullets, you will not reach these levels.

In your case you are using his rifle and loads. I have always found case tolerances to loose with the Lazzeroni brass to produce consistant results at long range. While some has been very good others have been very bad and you never know what you will get from one box to the other and for +$2.00 per case, that is simply not acceptible in my opinion.

As far as your velocity lose, its hard to say for sure, loosing 400 fps is a dramatic velocity loss for sure.

The problem with some barrels and using Moly coated bullets or any other coated bullets for that matter is that sometimes it take a few shots for the velocity to stabilize and get consistant. This is one reason I do not like coated bullets except for rounds like the 50 BMG where controling copper fouling is a must.

I would say there are several areas to look at.

First off, with 800 rounds down the tube, you may or may not have a throat erosion problem. Really depends on how those 800 shots were fired. IF you kept the barrel relatively cool during shooting, I would be suprised if you were even half way to the end of your barrel life.

Course with a case this size, if the barrel did get heated up, and was still shot when hot, the throat may be eroaded quite badly.

This is the most obvious reason for velocity loss of this degree but it does not happen all at once.

Some other factors that may be in play are:

-Are you using a different lot of IMR-7828 then when you developed your first loads? If so this can often change velocity a significant amount in a case this large.

-Are your X bullets being seated to the same depth as your first load. Not measured with Over All Length but at the full diameter of the bullet at the beginning of the ogive.

The X bullet is extremely sensitive to seating depth, any solid bullet is. Even a change of .020" can dramatically drop or raise velocity(pressure). Another reason I do not use the X bullet, they are simply to finicky to shoot.

Lot to lot variations in bullet shank length are common to a small degree, this can effect the distance from the full diameter of the bullet to the origins of the rifling, changing pressures from one pot of bullets to another.

In my honest opinion, using a 150 gr bullet in a 30 cal magnum case with a case capacity of +100 grains is really a waste of alot of horsepower. Sure over 500 yards they are flat shooting as hell but past that they really start to drop off.

If I were you, before I did anything as far as rebarreling the rifle, I would get a box of 180 gr Accubond bullets and test them with H-Retumbo. My brother has the Sako in the Warbird and with this powder and bullet was able to hit +3500 fps with groups ranging from the 1/2 to 3/4 moa range with great consistancy.

Big cases are quite pissy with light bullets driven very fast. It seems anything of a weak link is magnified dramatically with a light bullet driven to very high velocities.

Whereas the heavier bullets can be driven to very good velocities and just seem to settle the big cases down as far as an accuracy standpoint is concerned.

I have never found the X bullets to be accurate enough and consistant enough for me to recommend them to my customers for use in the rifles I build for them.

For a rifle like yours that cost what it did to only shoot in the 1 moa range would just about make a guy sick. This is not a shot at you at all but are you being effected by the recoil and blast of this big 30 magnum? Does teh rifle have a brake fitted to the muzzle?

All of the things I have listed would probably not equal a 400 fps loss in velocity but the drop is just over 200 fps from your 3493 fps to your 3729 fps average to start with. This could easily be a result of a combination of the above listing.

To be honest and you probably do not want to hear this but personally, if you rebarrel the rifle, I would drop the Warbird adn go with something else. Even the 30-378 Wby or a 30-338 Lapua Improved which is basically a 7.82 Warbird would provide much better consistany from a brass stand point and its cheaper to buy as well.

Still before you do anything I would highly recommend dropping the X bullet and testing some Accubonds or something on that line. Load them off the lands about 0.010" to 0.015" to start with and then you can adjust the seating depth from there to see how they respond on target.

You will not get the screaming velocity with this bullet weight but if your rifle did not hit 3550 fps I would be suprised using Retumbo. Also, if your rifle does not shoot them inthe 3/4 moa or less range I would say its time for a change in barrel.

Couse if your rifle has never shot better then 1 moa, it may need to be torn down adn rebuilt with a quality accurizing job.

The cheapest step is to try a new bullet, then go from there is that does not work.

If it comes to rebarreling the rifle, find a smith that builds extreme accuracy rifles for a living. There are several on the board alone that do this including myself.

I assure you, that if you ordered one of my rifles it would not leave the shop until it was cutting 1/2 moa groups and I know that is teh standard from the other smiths on this board as well. You should not have to settle for 1 moa groups from a rifle that cost that much money. We could build one for much less that would shoot far better I assure you.

Good Shooting!!!

Kirby Allen(50)
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Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

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Web Page: www.apsrifles.com

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  #3  
Old 01-21-2005, 06:30 PM
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Re: Drop in Velocity?

Fiftydriver, Thanks for info

When you say the case tolerances are to loose do you mean in case weight.

You are correct about the Moly coated bullets. My first shots after cleaning the barrel were 2 inches high every time and then they would come down to the point of aim after 3 or 4 shots this always bothered me.

While we are talking new barrel, I spoke with Gary Schneider today who made the original barrell on the gun and he said that the #5 barrel I have on the gun may be " a little whippy" he sugested that if I did not mind the weight on my gun He would put the largest barrel the Mcmillian stock would hold. He also suggested shooting the non coated bullets.He thought that may be a problem with the 1moa groups.

I found some 180 Accubonds today but no Retumbo.
I also have no load data for the retumbo. But here is what I do have
Max Load data from Lazzeroni
180 Grain Nosler Partition 3.600 O.A.L. @ 70F

DuPont Min Max F.P.S. P.S.I.
IMR 7828 90GR 98.5GR 3464 66,100
Alliant
Reloader 25 94GR 104GR 3560 66,400
Accurate
8700 108GR 118GR 3481 66,700

Can anyone use this to give me a starting point for Retumbo

As far as the aol for that load If I use a fired case and tighten up the neck and insert the case in the chamber I come up with 3.760 with the accubond but I dont think any aol over about 3.650 will fit in the mag.

The rifle has a break. I shot it the 1st 300 rounds without the break screwed on because I thought it would affect the accuraacy. Then I shot it with the break and you do not have to wory about me shooting without the break anymore.WHAT A DIFFERENCE A BREAK MAKES. Do not get me wrong when I say it shoots 1moa I have shot 3 shot groups with it less than 1/2 moa and my best group is less than 1/2 inch at 300 yards but the next group will be 3 inches at 300 yards. It just does not seem to be consistant.Maby it is the Coated X bullet.

Again thanks for taking the time to help me with my problem.

PS. If I deside to keep the warbird do you have a reamer to chamber the rifle.
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Old 01-21-2005, 08:25 PM
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Join Date: Aug 2004
Location: utah
Posts: 302
Re: Drop in Velocity?

After reading Fiftydrivers post I agree with him on almost every point,if you do have to re-barrel get as far away from lazzeroni chambers and brass as you can,the first thing to trash can is Barnes x bullets (I live only 7 miles away from Barnes and wish I could support a local company but every time I have used there product I have been disappointed)
the only point I disagree with Fiftydriver on is if you have to re-barrel he suggested a 30-378wby, I think even a 30-378wby is too much powder capacity for a 26" barrel. I have seen several 300RUM's that shoot faster than a 30-378 with far less powder. personally I will stick with my dirty old school 300wm.
On this topic one thing I find fascinating is that I have several shooting friends that shoot the lazzeroni warbird and they have all been convinced (or brain-washed)to shoot 150gr bullets in this cartridge, I see no logic to it at all it would be like shooting a 200gr flat base in a 50bmg wasting all that powder going so fast with no B.C.
If some one has a logical answer I'm listening
B
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Old 01-21-2005, 09:17 PM
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Re: Drop in Velocity?

Well here is mine. Not a very good one.

Lazzeroni suggest the 150 x bullet and because I purchased a gun from them I thought they would know there guns better than anyone else. I thought that the 1-12 twist barrell was better suited for bullets under 168. Also the 150 had less recoil than the 180,s.


[img]/ubbthreads/images/graemlins/crazy.gif[/img]
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  #6  
Old 01-21-2005, 10:37 PM
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Join Date: Aug 2004
Location: utah
Posts: 302
Re: Drop in Velocity?

bcraft1111,
Your 12" twist is perfect for a .308 win to shoot 150-168gr. bullets fast and efficient for the case size, a Lazzeroni warbird is a waste with these size bullets, it would be like sending Rosie O'Donnell into Mc Donald's for a 79cent hamburger, this girl needs a double quarter pounder with cheese (180,200+ gr)
lazzeroni missed the boat but people buy into the leading edge hype like this and carbon fiber fluff barrels.
have a good weekend B
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Old 01-21-2005, 10:48 PM
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Re: Drop in Velocity?

Bcraft1111,

What I was referring to as far as loose tolerances in the brass really is not the weight of each case, or the volume. They seemed to be acceptible in consistancy for this large of a case, suprisingly.

What I was referring to was body wall and case neck thickness. Some Lazzeroni brass I have measured in the case wall thickness just ahead of the solid case head varied by as much as 0.020" from one side of the case to the other. This is impressively bad consistance.

Others would be identical but there were enough bad ones in the lot of brass I measured to show the true colors of the brass quality. About 15% would be off by this much.

Case neck thickness also varied by up to 0.001" from side to side. Again, some was very consistant, others were pathetic in quality.

When you drop that kind of money on each case, they better be quality, all of them!!!

Schneider barrels are surely quality barrel, only bad thing the barrel is only as good as the machining in the rifle. I have not looked at enough Lazzeroni rifles to determine the quality of the machining in their rifles but this sounds like a mechanical problem to me.

Gary does have a point to the barrel whip issue but at only 27" of barrel length, a #5 contour is a pretty stiff barrel espeically when using 150 gr class bullets.

I use Lilja #6 contour 30" stainless barrels on my Extreme Sporters chambered for my Allen Magnum rifles and they print sub 1/2 moa consistantly and in the 1.5" range at 500 yards. True these are slightly smaller case capacities but they are longer barrels as well. I also totally free float the full barrel length and never have a problem with barrel whip, even in the 270 AM with the 130 gr bullets loaded to 3850 fps.

I also use Lilja #5 contours on my conventional sporters for rounds such as the 300 RUM which is only about 50 to 75 fps if that behind the Warbird in equal length barrels, never had a problem.

I will get you some load data from my brother that he developed in his Warbird with the 180 gr Accubond. He is getting some great groups out of his Sako.

Of the powders you list, RL-25 would be the best, IMR-7828 can be temp sensitive and 8700 can be a little dirty until top pressures are reached. Rl-25 is relatively temp resistant and will produce good velocities.

Retumbo will perform better then any of them in consistancy and top velocity and also temp resistant.

How close are you seating the X bullet to the origins of the rifling? Unfortunately, I would not recommend getting any closer then 0.050" off the lands for safety sake.

Your rifle obviously has a pretty long throat if the Accubond can be seated out to 3.760 on the shorter then full length Warbird case. Unfortunately this will effect accuracy unless the throat is cut to tight specs which by the sounds of it it is not.

For curiousity sake though, I would seat the Accubonds as long as possible and feed them single shot and see how they shoot. IF your groups shrink dramatically, you may want to look into having a longer mag box fitted if possible.

I do not have a Warbird reamer in shop but if you wanted a barrel chambered I would get one in.

If your barrel will shoot well at times and not at others, I would say we are dealing with either a mechanical vibration consistancy problem or a load dimension problem such as bullet seating depth away from the rifling.

Again, get a know accurate bullet and full test that first. The Accubonds already have a much better accuracy reputation then the X bullet ever will.

I would also like to warn you about that load data you listed, When we were developing loads in my brothers Warbird, Retumbo was not yet released and RL-25 was the powder for this round. Well, he was blowing primer pockets out at 102 gr and only 3450 fps with RL-25. Sure this was in the Sako rifle but I would be cautious about using Lazzeronis top loads.

HE lists his Warbird as faster then the 30-378 Wby which is about 15 gr larger in capacity then his case, physics are physics, this ain't possible without higher pressures.

I will get you some safe load data to start with the 180 gr Accubond and Retumbo.

Good Shooting!!

Kirby Allen(50)
__________________
Kirby Allen(50)

Allen Precision Shooting
Home of the Allen Magnum, Allen Xpress and Allen Tactical Wildcats and the Painkiller Muzzle brakes.

Farther, Faster and Flatter then ever before.

Web Page: www.apsrifles.com

allenmagnum@gmail.com
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