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Doesn`t make sense ??? - Redwoodcity1955 - 05-01-2022
I`m running Lapua cases.
Lapua Scenar 123 HPBT.
CCI #200 Primers.
28.5 GR. Varget.
Wilson 22" Barrel.
Cryptics Coating BCG.
Deviation is under 10
Some of the FPS are identical !
The problem is at 100 yards the spread is more that 2" ???
What is going on here ???
Please help I`m stumped ???
Doesn`t make sense ??? - VASCAR2 - 05-01-2022
Curious your using CCI 200 primers which are large rifle primers. Are you using Lapua 6.5 Grendel brass (small rifle primers) or fire formed brass with large rifle primers. Varget is good powder but bulky which limits its velocity in the 6.5 Grendel. With Varget you might not be seating the bullet deep enough to get good accuracy as Ive read Scenar like to be seated off the lands. Its possible your barrel just doesnt like this bullet/powder combination. You might have not hit on the right node for that powder charge. Sierra list a maximum charge of 27.7 grains of Varget with a 123 grain SMK with Winchester small rifle primers in their 24 universal receiver in the 6.5 Grendel.
Also Id double check to make sure the scope and mount are tight. Id also make sure the gas block is not hitting the hand guard and the gas tube is properly aligned. As a last resort you might try shooting the barrel with no muzzle device (FH, Brake or Suppressor).
Doesn`t make sense ??? - myrifle - 05-01-2022
Change too cci450 primers, if that doesnt fix it.
Adjust seating depth in steps of 5 thousands shorter and longer for a distance of 20 thousands.
Doesn`t make sense ??? - Redwoodcity1955 - 05-01-2022
VASCAR2 Wrote:Curious your using CCI 200 primers which are large rifle primers. Are you using Lapua 6.5 Grendel brass (small rifle primers) or fire formed brass with large rifle primers. Varget is good powder but bulky which limits its velocity in the 6.5 Grendel. With Varget you might not be seating the bullet deep enough to get good accuracy as Ive read Scenar like to be seated off the lands. Its possible your barrel just doesnt like this bullet/powder combination. You might have not hit on the right node for that powder charge. Sierra list a maximum charge of 27.7 grains of Varget with a 123 grain SMK with Winchester small rifle primers in their 24 universal receiver in the 6.5 Grendel.
Also Id double check to make sure the scope and mount are tight. Id also make sure the gas block is not hitting the hand guard and the gas tube is properly aligned. As a last resort you might try shooting the barrel with no muzzle device (FH, Brake or Suppressor).
Thank You for responding !
The brass is factory new and the primers are 400's "sorry" !
Also, this high end build is in the AR format.
I will check everything you have mentioned as well.
My other AR builds in the 223 and 308 deliver consistant .5 moa results at 100 yards.
FYI, this current build has only 150 rounds plus / minus !
Doesn`t make sense ??? - Redwoodcity1955 - 05-01-2022
I just noticed, the brake had come loose !!!
Doesn`t make sense ??? - Klem - 05-01-2022
Redwoodcity1955 Wrote:I just noticed, the brake had come loose !!!
Red,
It is probably more than that.
Varget is a slow, bulky powder for a small calibre and 22" (short) barrel. At a standard AR magazine length you are 110% overloaded. I doubt you can even seat a bullet or if you can it is crunched up so much that you will have consistency and pressure issues issues just from that alone. There is 5% unburnt powder coming out the end of that barrel so the idea you are recording velocities that are exactly the same is rare. Single digit standard deviations still imply there is a range of velocities in a string, albeit close.
It is a hot load. QL is showing 58K lbs, but at 110% crushed who knows what it really is.
With due respect, making the mistake of detailing the wrong primer and brakes that are coming loose. 110% overloading cases and that is where your 2" group is. Along with that there is the quality of barrel and shooting technique that is unaccounted for.
Please be careful.
Doesn`t make sense ??? - LRRPF52 - 05-04-2022
Klem Wrote:Red,
It is probably more than that.
Varget is a slow, bulky powder for a small calibre and 22" (short) barrel. At a standard AR magazine length you are 110% overloaded. I doubt you can even seat a bullet or if you can it is crunched up so much that you will have consistency and pressure issues issues just from that alone. There is 5% unburnt powder coming out the end of that barrel so the idea you are recording velocities that are exactly the same is rare. Single digit standard deviations still imply there is a range of velocities in a string, albeit close.
It is a hot load. QL is showing 58K lbs, but at 110% crushed who knows what it really is.
With due respect, making the mistake of detailing the wrong primer and brakes that are coming loose. 110% overloading cases and that is where your 2" group is. Along with that there is the quality of barrel and shooting technique that is unaccounted for.
Please be careful.
28.5gr of Varget under the 123gr Scenar is the published max load by AA dating back many years to the initial test breech work Bill A. did for 6.5 Grendel.
How many times is this going to happen where the QL numbers are listed when someone is using published data?
Check with published data before referencing anything in QL. QL is just so far off the mark in so many cases, as to be disregarded.
Im not sure why anyone would reference it for 6.5 Grendel.
Doesn`t make sense ??? - Klem - 05-04-2022
Along with a bunch of broken bolts early in the evolution of this calibre.
I poured 28.5gns of Varget (AR2208) into a case and it comes up to the datum line of the shoulder. QL is correct, it is a seriously compressed load. Pressure aside, 5% unburnt powder is flames out the front and erosion of suppressors if used. Flames out the front is a recipe for inconsistent performance.
Once again we have the conflict-of-interest of a person trying to sell his loading book slamming the competition, a computer program. I put it to you that neither is perfect.
Doesn`t make sense ??? - myrifle - 05-04-2022
LRRPF52 Wrote:28.5gr of Varget under the 123gr Scenar is the published max load by AA dating back many years to the initial test breech work Bill A. did for 6.5 Grendel.
How many times is this going to happen where the QL numbers are listed when someone is using published data?
Check with published data before referencing anything in QL. QL is just so far off the mark in so many cases, as to be disregarded.
Im not sure why anyone would reference it for 6.5 Grendel.
I have to agree with Klem on this one.
After doing some very detailed work with Varget in my cz grendel. Anything approaching 28.4 grains are more and my coal length had to be way past 2.300 to have room to not crush powder.
Now I had the mag length too run such long coal lengths but at normal ar15 mag lengths, 28.5 grains of varget is a maxed out crunchy load.
Doesn`t make sense ??? - VASCAR2 - 05-05-2022
I just checked my Hornady data for Varget and they list a max charge 28.9 grains Varget with 120-123 grain bullets. I have used Varget in the 6.5 Grendel but I found other powders I liked better. Sierra seems pretty conservative with some of their data.
Doesn`t make sense ??? - Klem - 05-05-2022
Varget (2208) is a slower, bulkier powder compared to the more popular choices. It is used in 308 and Creedmore with typically longer barrels so it can fully burn prior to exit. I use it in 6.5x47. I have used it in a smaller calibre: .223, but with long 30" F-Class barrels, so it can burn slower and accelerate the bullet the full length for max velocity. In 223, with Varget, use of a drop tube is also needed. In that I am using a bolt gun with their strong bolt lugs and thicker breeches than an AR.
In shorter barrels and regardless of the action, it's burning out the end. This will be one influencer of the OP's results on target.
As for compressing powder past 103%, if you can buy less bulky powder the gun and results on target will thank you.
Doesn`t make sense ??? - LR1955 - 05-05-2022
Klem / Guys:
I understand that Varget is too slow and bulky to be efficient in a Grendel.
However, everyone here who has used it seems to get some very good accuracy results although the velocities were a good 100 fps slower than a more efficient powder.
I recall using Varget in some 7.62 X 39 brass with some 120 Sierra's many years ago and a compressed load brought me up to about 2500 fps from a 22 inch barrel. I thought it not quite right so tried it again on a different day and got the same results. Good to go? Negative. The way the shot sounded was not right and the primers were pretty flat so I didn't do it again. I figured the compressed load resulted in the velocity but that it was probably way overpressure so didn't mess with it anymore. This was before Quick Load and the only thing we had to go was Alexander's load data.
I don't recommend any compressed loads with anything, no matter if the rifle is an AR or a bolt rifle. Way too risky for only a very slight gain in velocity and no improvement in accuracy. Not good for the brass life either.
With Varget in the Grendel, Alexander had a number of loads using Varget. I don't see anything wrong with using Varget as long as the shooter doesn't go with the compressed charges.
LR55
Doesn`t make sense ??? - mdram - 05-05-2022
Redwoodcity1955 Wrote:I`m running Lapua cases.
Lapua Scenar 123 HPBT.
CCI #200 Primers.
28.5 GR. Varget.
Wilson 22" Barrel.
Cryptics Coating BCG.
Deviation is under 10
Some of the FPS are identical !
The problem is at 100 yards the spread is more that 2" ???
What is going on here ???
Please help I`m stumped ???
how did you come up with that load?
did the workup show it to have the best grouping?
have you done a seating depth test yet?
Doesn`t make sense ??? - LRRPF52 - 05-05-2022
myrifle Wrote:I have to agree with Klem on this one.
After doing some very detailed work with Varget in my cz grendel. Anything approaching 28.4 grains are more and my coal length had to be way past 2.300 to have room to not crush powder.
Now I had the mag length too run such long coal lengths but at normal ar15 mag lengths, 28.5 grains of varget is a maxed out crunchy load.
There is nothing wrong with compressing powder. This is one of the biggest misconceptions of reloading, that compressed loads are somehow bad.
Here is Hodgdons take on compressed loads:
Quote:COMPRESSED LOADS
Normally a pistol or rifle shellcase is considered full, or 100% loading density, when the powder charge sits at the base of the bullet when the bullet is fully seated. It is possible with some powders and cartridges to increase the powder charge slightly above this point, such that when the bullet is seated it actually compresses the powder charge slightly. This condition is known as a compressed load.
Hodgdon notes in its reloading data if the subject charge is a compressed load. A full case, or lightly compressed charge is an ideal condition for creating loads with the most uniform velocities and pressures, and oftentimes, producing top accuracy
If you look at their published compressed load data, there arent any of them that exceed 50,000psi, and they have a lot of them.
Hodgdons publishes at least 30 compressed loads for 6.5 Grendel from 85gr Sierra up through 123gr Sierra.
They range from 42,400psi to 50,000psi.
They have more compressed loads than not.
Doesn`t make sense ??? - LRRPF52 - 05-05-2022
Klem Wrote:Along with a bunch of broken bolts early in the evolution of this calibre.
I poured 28.5gns of Varget (AR2208) into a case and it comes up to the datum line of the shoulder. QL is correct, it is a seriously compressed load. Pressure aside, 5% unburnt powder is flames out the front and erosion of suppressors if used. Flames out the front is a recipe for inconsistent performance.
Once again we have the conflict-of-interest of a person trying to sell his loading book slamming the competition, a computer program. I put it to you that neither is perfect.
Nope. We have someone who keeps referencing demonstrably-proven bad data source (Quick Load) as a constant fall-back when there is known, pressure test breech data from multiple industry sources who have done that specific testing with 6.5 Grendel.
QL has zero pressure test breech testing with 6.5 Grendel, and is a theoretical internal ballistics engine lacking real world data to support the numbers it kicks out for this cartridge.
If you had looked at Alexander Arms data and noticed that they have the same load and bullet combo as the OP, rather than immediately going to QL, you would have asked,
Hmm, one of these is way off from the other, which is correct?
Again, why are you referencing disproven/invalid data sources when there are published, known quantities?
QL is invalid and off by thousands of PSI. Remember the last thread where we did this? It was off by a minimum of 9,000psi to over 10,400psi.
Where does it compute logically that anyone would want to use it as a reference after knowing that?
Doesn`t make sense ??? - LRRPF52 - 05-05-2022
31 out of 40 of Hodgdons published, calibrated pressure test breech-derived loads for 6.5 Grendel are compressed.
None of them exceed 50,000psi.
QL says many of those loads are 58,000psi and much higher.
Conclusion: QL is a waste of time for this application, totally invalid, of no use for the layman trying to get an idea of whats going on in their chamber.
Doesn`t make sense ??? - Klem - 05-06-2022
2208 (Varget) is the powder I use for 223 out to 1,000 yards. I have no issues with its accuracy out of thick, long match barrels. It is also a single-based powder so less variation between hot and cold/winter and summer.
I use QL in all my calibres along with other sources of info and have been doing it for years with no issues. I get that some shooters are suspicious of computers and their programs but it is the 21st Century. Discounting data because it is a simulation is fraught with a lack of reason. Your own government simulates nuclear explosions on computers because of test bans and restrictions. This is no different and certainly does not justify the exaggerated hate.
If a load is more than 103% compressed and if there is unburnt powder coming out the end it is recipe for less than optimum results. Alexander or anyone else could not convince me in a million years otherwise. Hogdon's copies word for word from its supplier, ADI/Thales and I'd be the first to admit Australia has not had a long familiarity with Grendel due to the lack of AR's in the community. There is not a demand for Grendel in bolt guns either. I doubt if ADI did a lot of considered testing for Grendel and certainly no history of it.
Doesn`t make sense ??? - StoneHendge - 05-06-2022
Klem Wrote:Discounting data because it is a simulation is fraught with a lack of reason. .
Data by definition is known facts. The output of simulations is a not facts.
Doesn`t make sense ??? - Klem - 05-06-2022
StoneHendge Wrote:Data by definition is known facts. The output of simulations is a not facts.
Data is information which researchers use as fuel to analyse, hopefully resulting in phronetic wisdom.
I don't think anyone is saying the output of a simulation is factual, or I think you mean matches [exactly] reality. Just because it does not match reality to your definition of precision does not mean it is useless. There are variables that QL does not take into account, plus the inherent range of pressures and velocities with subsequent firings of the same load.
I find it a useful aid and has served me well. It has saved a lot of money and I will continue to use it.
Doesn`t make sense ??? - grayfox - 05-06-2022
Data consists of individual, observable or recordable facts or numbers or quantities, from whatever source. How "close to reality" or how trustable that Data is, is another question entirely.
And, to be fair to both "sides", while Hodgdon speaks of "slightly compressed," or "lightly compressed," [neither of which is really quantifiable by the way], and Klem speaks of "110%" compressed. Even Hodgdon would not recommend 110, I would bet a donut on that.
So in that respect the 2 positions are not really all that different. The crux of what the load might be lies in how much it actually was compressed for Alexander (let alone how much so for Redwood), vs what Klem (or other simulations) finds in their simulations.
I have some loads for my grendel modeled on Grt, and they are not Lapua brass, but dropping case volume/capacity down by 1 grain, loading in the 123 scenar to 2.265 OAL and 28.5 of varget comes up with 101.3% and 57ksi... which by definition would qualify as compressed, and above max.
So, from at least 5 different sources here, we have 5 pronouncements as to this "load"
1. Bill Alexander, unknown % case fill but marketable load at 28.5 (it might also be added that we may not know if AA is still loading this round at that load... sometimes lawyers have you back off to lower loads for liability reasons... )
2. Klem's QL model, which has it at 110% compression, 58 Ksi
3. My Grt which has a 101.3%, 57ksi
4. OP's load of unknown % fill/compression.
5. A5's load experiences, unknown pressures but 28.4-28.5 loaded out to 2.300" COAL. Somewhere at/above 100% fill give or take.
IF a load were at 110% compressed, THEN Klem's conclusions would rightly follow.
If compressed to say 102%, maybe not so dangerous/unpredictable but could still be overpressure. From my model, 27.7 gr is max pressure at 51.8 ksi, 98.5% load fill. Now this is a model, granted, but now you have this "datapoint" to consider.
The bottom line is that we seek a safe load from all perspectives. And Redwood, you might want to note that the Grendel does not exhibit overpressure indications in brass until you are way over. So lack of swipes and "rounded" or "unflat" primers, do not necessarily equate to being < 52 ksi.
And note that all of the above scenarios, except for OPs' are merely simulations or representations of his actual barrel-results, whether computer-program or "someone else's" barrel -- they are all "approximates," "estimations," of the OP. As we always say, ymmv.
Some clarifications from Redwood would be in order.
1. What OAL for the cartridge; did you work up to this or just plunge in at 28.5... and if worked up to, then what did the other results do. What kind of re-checks/re-torques did you do for the optics/mount, barrel install, etc. What kind of trigger does this rig have.
2. What kind of observation as to whether the load was not compressed, compressed, too compressed, or what.
3. Did you retest after removing the loose brake from the equation. ps, crush washers cause uneven torque on the muzzle, so use either an Accurate Washer system or jam nut or time it without crush washers...
3. What other loads/rounds have you shot from your rifle, what were the results.
4. What chrono results did your loads present.
5. Did you do a seating length test, varying the depth to see the differences in grouping.
6. 6.5 Grendel in an AR is better served with harder cup primers, like cci450, cc41's, Fed 205AR's. I don't think this would cause what you're seeing in grouping but it's a comment anyway.