velocity

swarovski

Well-Known Member
Hi all, ive recently got a 6.5 06, I loaded it to sierra accuload powder measures,it really seems quite pokey with 140gr bullets, am yet to chrony, with aporox 100yd zero, when i mean approx zero i changed from 139gr scenars too 142gr smks,my elevation at 1000yds was 6.7 milrad,calculating the elevation to my reckoning bullet speed would be 3075fps, is this possible from a 26 inch 1 in 200mm twist, atb swaro
 

bewsher500

Well-Known Member
that is factory 270/25-06 speed with a shorter barrel albeit slightly lighter bullets in most cases
 

JMS906

Well-Known Member
Hi all, ive recently got a 6.5 06, I loaded it to sierra accuload powder measures,it really seems quite pokey with 140gr bullets, am yet to chrony, with aporox 100yd zero, when i mean approx zero i changed from 139gr scenars too 142gr smks,my elevation at 1000yds was 6.7 milrad,calculating the elevation to my reckoning bullet speed would be 3075fps, is this possible from a 26 inch 1 in 200mm twist, atb swaro

It seems unlikely. You don't say which bullet you are using or which powder. But the following is indicative.

Quickload states that with a Hornady AMAX 140g bullet, 61.0g of N165, and in a 26" barrel you would get 3019 fps but with a peak pressure of 61,800 psi. The maximum service pressure is 63,000 psi so you would be pushing the envelope. With just another 0.1g of powder, you would be producing 3023 fps (a gain of 4 fps) but at a cost of 62,200 psi. I'm not sure you could get 61 grains of powder into the 6.5-06 case but even if you could, it would be foolish to do so without working up from, say, 59.0g which should deliver 2930 fps at 55,800 psi.

I hope this helps.

-JMS
 

tackb

Well-Known Member
It seems unlikely. You don't say which bullet you are using or which powder. But the following is indicative.

Quickload states that with a Hornady AMAX 140g bullet, 61.0g of N165, and in a 26" barrel you would get 3019 fps but with a peak pressure of 61,800 psi. The maximum service pressure is 63,000 psi so you would be pushing the envelope. With just another 0.1g of powder, you would be producing 3023 fps (a gain of 4 fps) but at a cost of 62,200 psi. I'm not sure you could get 61 grains of powder into the 6.5-06 case but even if you could, it would be foolish to do so without working up from, say, 59.0g which should deliver 2930 fps at 55,800 psi.

I hope this helps.

-JMS

not a mile away then ?

sounds like great medicine for all our deer species!
 

swarovski

Well-Known Member
139gr scenars,142gr smks,140gr smks,140gr nosler customs,50,6grs of n160, have started pulling and reducing loads as primers were showing signs of pressure, I did load same bullets with 50.6grs of rel 19, still the same, feels too hot, kept a few to chrony out of curiosity
 

Muir

Well-Known Member
139gr scenars,142gr smks,140gr smks,140gr nosler customs,50,6grs of n160, have started pulling and reducing loads as primers were showing signs of pressure, I did load same bullets with 50.6grs of rel 19, still the same, feels too hot, kept a few to chrony out of curiosity

Until you chrongraph the loads you're flying in a fog. I'd concentrate on getting that done asap. Dual chrongraph readings would allow you to calculate the actual BC of your bullet for your location.~Muir
 

Yorkie

Well-Known Member
It seems unlikely. You don't say which bullet you are using or which powder. But the following is indicative.

Quickload states that with a Hornady AMAX 140g bullet, 61.0g of N165, and in a 26" barrel you would get 3019 fps but with a peak pressure of 61,800 psi. The maximum service pressure is 63,000 psi so you would be pushing the envelope. With just another 0.1g of powder, you would be producing 3023 fps (a gain of 4 fps) but at a cost of 62,200 psi. I'm not sure you could get 61 grains of powder into the 6.5-06 case but even if you could, it would be foolish to do so without working up from, say, 59.0g which should deliver 2930 fps at 55,800 psi.

I hope this helps.

-JMS

Hi JMS.
I know very little about Quickload but the 61.0 Grains it has given you is a full 10 Grains over the Nosler Max Load for the 140 Grain Bullet with N165 in the 6.5-06. That would seem a heck of a discrepancy. Am i misunderstanding something?

Yorkie.
 

JMS906

Well-Known Member
Hi JMS.
I know very little about Quickload but the 61.0 Grains it has given you is a full 10 Grains over the Nosler Max Load for the 140 Grain Bullet with N165 in the 6.5-06. That would seem a heck of a discrepancy. Am i misunderstanding something?

Yorkie.

No, you are not missing anything. I didn't look in any reloading manual. The example I gave was simply to illustrate what was required to deliver the velocity 'swarovski' was seeking, and also to indicate that it means playing around at maximum service pressures - presuming that his barrel behaves as QuickLoad suggests. If his barrel produces pressures higher than QuickLoad predicts, then he would be exceeding the design limits of his rifle and heading towards proof loads pressures. Which is why I said it would be a foolish thing to do.

Moreover, using the appearance of spent primers as a means to guage (I mean guess) pressures is also foolish because it is unreliable. Page 55 of Speer's 13th Reloading Manual explains why and presents a nice photograph of three spent primers all of which look the same. One is a soft load, one is a normal load, and one is 20% over load. But they all look the same. Similarly, I have had very flattened primers in perfectly normal factory loads. Yes, if your normal load doesn't flatten primers and a higher powder charge does flatten the primers - all other components being the same - it indictaes higher pressure but not necessary excessive pressure.

OK, looking in the Hornady reloading manual (6th edition) it indicates normal velocities for the 6.5-06 with a 140g bullet are 2500-2800 and maximum loads deliver 2900fps. Maximum load for N165 is 50.4g, which is 10.6g below what is required for swarovski's 3075 fps target. Therefore his desired velocity appears unobtainable within service pressure.

-JMS
 

Yorkie

Well-Known Member
Hi JMS.
It was the difference between the Quickload and the Manual Data that suprised me. If Quickload predicts that 61 grains is running at maximum but safe pressure it would seem to differ greatly from Lab tested Data in the Manuals. Just how accurate is Quickload?

Yorkie.
 

Whitebeard

Well-Known Member
With all due respect, quickload should not be used as a stand alone source of reloading data, use it in conjunction with at least one reloading manual where the loads have actually been tested and do not rely on computer modelling.

Ian.
 

Muir

Well-Known Member
With all due respect, quickload should not be used as a stand alone source of reloading data, use it in conjunction with at least one reloading manual where the loads have actually been tested and do not rely on computer modelling.



Ian.

I agree. Quick Load has been noted to have some irregularities in it's results in the past. You should never use it for loading data.~Muir
 

Yorkie

Well-Known Member
I was just wondering what was the point of it when it gives you 20 per cent over maximum book loads?

Yorkie.
 

JMS906

Well-Known Member
Hi JMS.
It was the difference between the Quickload and the Manual Data that suprised me. If Quickload predicts that 61 grains is running at maximum but safe pressure it would seem to differ greatly from Lab tested Data in the Manuals. Just how accurate is Quickload?
Yorkie.

I've found QuickLoad to be a very useful accessory to industry published loads. When deciding on a load, I refer to the industry manuals (either printed or online) and also use QuickLoad as a cross reference. I have manuals by Hornady, Speer, Sierra, Vihtavouri, Hodgdon, Swift, A-Frame and others and in some cases, several editions. What I find is that the manuals tend to become increasingly conservative over time. For example, an older edition might havea load range of, say, 42.0 - 46.0 grains and a later edition reduces that to say 41.0 - 44.0 grains.

In terms of accuracy, QuickLoad's predicted velocities seem to be nearer the mark than the printed manuals' predicted velocities, which are over optimistic (as are the claimed ballistic co-efficients). If you load for several types of ammunition, rather than just one rifle, QuickLoad is worth having. It also comes with QuickTarget for calculating external ballistics, and that's handy. I know you can get apps for mobile phones these days.

What QuickLoad cannot do for you is tell you what pressure your barrel produces. It can only make a prediction based upon its 'model' barrel. If you want to know what true pressure your particular handload produces, send ten round to the Birmingham Proof House who, for a reasonable fee, will test your ammo and produce a technical report for you. The last time I attended the Proof House's laboratory, which was at least five years ago, the fee was around £65+VAT. The thing to do is prepare three loads of 3 rounds each. Speak with the lab staff. Alternatively, you could buy a PressureTrace kit RSI - PressureTrace I've got one and it's quite revealing. [You either calibrate your barrel using factory loads or send a sample to the Proof House who will give you an absolute pressure reading.] Even if you don't calibrate the device against a known pressure, if one of your handloads indicates 50 kpsi and then next shows 60 kpsi, that's a real 10 kpsi increase. One of my handloads (with a slow powder in a .30-06) delivered two peak pressures, othe first as the bullet left the chamber and the second occurring as the bullet exited the muzzle. This is now a known phenomenon (see the PresureTrace website) and is cured by using a slightly faster powder.

-JMS
 
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swarovski

Well-Known Member
Hi jms, would be intresting to see what the quick load predicts my velocity from 142gr smk with 50grs of n160 through a 26 in barrel, I will post my fps when I get to chrony, atb swaro
 

Yorkie

Well-Known Member
Hi JMS.
A very thorough explanation, thank you.
As someone who uses Quickload did you find the 20% difference in the Book max and Quickloads suggested max suprising? Even taking the variables into account this would seem a lot.

Yorkie.
 

JMS906

Well-Known Member
Hi jms, would be intresting to see what the quick load predicts my velocity from 142gr smk with 50grs of n160 through a 26 in barrel, I will post my fps when I get to chrony, atb swaro

I would also need to know the case length (after trimming) and the loaded round's overall length. But supposing they are 2.794" and 3.340" respectively, Ql indicates an abnormally low pressure & velocity of 38.9 kpsi and 2570 fps, which looks suspicious. What were you expecting?

57.0f of N160 would put you at 2900 fps for 55.6 kpsi (max permitted 63.0 kpsi).

-JMS
 

JMS906

Well-Known Member
Hi JMS.
A very thorough explanation, thank you.
As someone who uses Quickload did you find the 20% difference in the Book max and Quickloads suggested max suprising? Even taking the variables into account this would seem a lot.

Yorkie.

There is a difference in the meanings of 'max load'. The reloading manuals meaning is "do not use any more than this" whereas the figures I calculated by QuickLoad were for a load that would reach the maximum permitted service pressure under SAAMI specifications. You would be utterly reckless to load ammo to that level. The only exception would be where you had submitted that load for testing by the Proof House and obtained a certifcate to the effect that the load did not exceed the maximum pressure in their test barrel, and even then you'd be nuts to do it. Apart from safety issues - how would you know that your rifle would not produce even higher pressures and/or break up - you would get reduced accurary. Best accuracy is generally achieved a few 100 fps below the book maximums.

-JMS
 

Muir

Well-Known Member
There is a difference in the meanings of 'max load'. The reloading manuals meaning is "do not use any more than this" whereas the figures I calculated by QuickLoad were for a load that would reach the maximum permitted service pressure under SAAMI specifications. You would be utterly reckless to load ammo to that level. The only exception would be where you had submitted that load for testing by the Proof House and obtained a certifcate to the effect that the load did not exceed the maximum pressure in their test barrel, and even then you'd be nuts to do it. Apart from safety issues - how would you know that your rifle would not produce even higher pressures and/or break up - you would get reduced accurary. Best accuracy is generally achieved a few 100 fps below the book maximums.

-JMS

The problem with Quick Load and real-world data is that QL does the math and says that in theory, a particular load will give, say, 60K pressure. That's nice, but it just doesn't work that way in a pressure gun. Powder manufacturers set maximum loads at the level which keeps 100% of the loads tested under the SAAMI ( or CIP) maximum levels. This is why cartridges that have a 60K ceiling for pressures might only list 56K for a MAX load with a given powder; that is simply as much powder you can put into the case without having pressure excursions over the SAAMI max. ~Muir
 
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