SIGforum.com    Main Page  Hop To Forum Categories  Reloading    Muzzle Velocity Question
Page 1 2 
Go
New
Find
Notify
Tools
Reply
  
Muzzle Velocity Question Login/Join 
Member
Picture of henryrifle
posted
Recently I purchased a Remington 700 Magpul in .308 when Remington offered a $150 mail-in rebate. My brother-in-law purchased one too.

Some of this is new to me and I have little experience for comparison purposes. So far, I've found a couple of loads that seem stable and yield sub-MOA results --but only just-- .7 to .8. All of this is using Lapua large rifle primer brass, GM210M primers, 175 gr. SMKs loaded at an OAL of 2.81" using Varget:

42.9 gr. Varget - Muzzle velocity as measured by Labradar 2625
43.0 gr. Varget - Muzzle velocity as measured by Labradar 2636
44.0 gr. Varget - Muzzle velocity as measured by Labradar 2675

I am getting very good SDs in the low single digits and ESs in the 8-20 range.

The average case capacity for my lot of Lapua brass is 54.68 grains of water and my brass measures 2.012" once sized. I use a redding Small Base Full Length Type-S die.

My velocities are, on average 50 FPS higher than Quickload indicates and consistently 35 FPS higher than my Brother-in-law's rifle. Our chambers measure very closely in length. The max COAL using the same projectile and the Hornady OAL Gauge measures .004" different. I have about 350 rounds through the rifle at this time.

There are some differences in components. He is using Nossler brass which does have about a grain more water capacity than my Lapua. He may also be using a different bushing to resize his brass.

Also, I only shoot suppressed using a Thunderbeast Ultra 9 direct thread-on 30 caliber suppressor. Also, I shoot prone with a heavy forward load on the bipod while my B-I-L shoots off a bench and sand bags.

I am not so interested in why my velocities are different from his but interested why they are so different from QuickLoad. What could cause that? Burn Rate has an impact but if I change the burn rate in QL to make the velocity match at one charge weight it does not match for any other charge weights.

I could be using too much neck tension I suppose. I am currently using a .335 bushing. I don't think that the GM210M primer is a hotter primer than a regular 210 but there is no provision for different primes in Quickload anyway.

I understand that QL is just another tool like Hodgdon's or Sierra's load data publications.

Thank you for your input.

Henryrifle
 
Posts: 442 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
Member
Picture of Blue68f100
posted Hide Post
QL is gust an educated guess as to what it will be based on the parameters you give it. Every barrel is different, no 2 a like, so that's expected. I'm in the process of turning a barrel blank now, discovered it has a tight bore. The normal std bushing does not fit, had to get a custom one ground. Which gives me high hope that this Shilen barrel will be a tack driver. Case volume plays an important part in how the pressure builds. Neck tension is just one option we have on slightly changing the pressure curve, timing. Then even minor differences in the chamber impacts it too.

I have 1 match barrel 223R that consistently produces higher velocities than the book values give. It's a tack driver, too. It ever makes the Hornady bulk 55gr FMJBT bullets look good.


David

P229R 9mm, Nitron, Beavertail Frame, Night Sights, DA/SA, SRT & Short Reach Trigger
 
Posts: 3405 | Location: Piney Woods of East Texas | Registered: November 08, 2008Reply With QuoteReport This Post
Knows too little
about too much
Picture of rduckwor
posted Hide Post
Excellent job providing useful data. Every rifle is different, lots of powder vary, temps vary. QL is a great tool but inexact. Don't get hung up on velocity changes until you change something important like powder lots. Pick the charge that is in the middle of the vertical variance of your satisfactory loads and rock on.

Shoot straight and enjoy.

RMD




TL Davis: “The Second Amendment is special, not because it protects guns, but because its violation signals a government with the intention to oppress its people…”
 
Posts: 18503 | Location: L.A. - Lower Alabama | Registered: April 06, 2008Reply With QuoteReport This Post
Member
posted Hide Post
I'm hoping that your first load is a typo and that it is indeed 42.0gr and not 42.9.

I went to hodgdon.com and looked at some loads with Varget and 175SMK. I will say that your velocities are pretty comparable to the site and you still have a grain to go if you need it. As the others above said, these are all approximation and barrels can be faster or slower.

Last year, the team did some load testing with Labradars and we discovered that my lot of Varget was more energetic than any of the others. With my Varget, I was getting 40FPS more than with another member's Varget in my cases, with my primers and my bullets in my rifle.

I'm just happy I bought a big enough lot to carry me from then until after the Worlds next month. After that, I may have to develop a new load with the next lot of Varget I will buy.

175gr SMK 42.0gr 2,583fps; 45.0 2,690fps. I interpolate that 43.0 would yield around 2,630 and 44.0, 2670fps.
 
Posts: 2650 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
Member
Picture of henryrifle
posted Hide Post
I really did mean 42.9 and your numbers match the same interpolation that I got from Sierra's manual but not close to QL using my observed case and projectile measurements.

Example from Quickload:
42.9 - 2586
43.0 - 2592
44.0 - 2647

Actual performance from my 22" barrel:
42.9 - 2624
43.0 - 2635
44.0 - 2675

I also tried the above with ADI AR2208 and got identical results.


I understand that QL is just a tool and you still have to shoot the rifle which is actually the fun part of the challenge but QL offers some great features if you can feed the program the correct data that matches the physical world and have it output results matching your measured results. I am thinking about features like helping you select other propellents that yield similar case fills, barrel time and MV. It would just save time but I have not been able to produce reliable results from QL that track with my actual results.

While I am posting pictures, you have to see this from yesterday:


Thank you for the help,
Henryrifle
 
Posts: 442 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
Knows too little
about too much
Picture of rduckwor
posted Hide Post
Those are good numbers as far as variance shot-to-shot go. What scale are you using to weigh charges?

I started a long diatribe about outcomes with my loads and deleted it as I realized my loads are my loads and yours are yours.

I thought about buying QL at one time as I enjoy make all the numbers fit and working up loads. I decided it would be just another time sink in a life already filled with time sinks.

I will be interested in your experiences tweaking it to match reality.

Good Luck,

RMD




TL Davis: “The Second Amendment is special, not because it protects guns, but because its violation signals a government with the intention to oppress its people…”
 
Posts: 18503 | Location: L.A. - Lower Alabama | Registered: April 06, 2008Reply With QuoteReport This Post
Member
posted Hide Post
Yes, those are great numbers indeed.

I never bothered with QL, probably because I am so focused on a single cartridge and load. I know that's strange for a techie like me who started his career keypunching COBOL and FOTRAN code on 80 column cards with an IBM 026, but it is what it is.

For me, the proof of the load is on the paper and when I see that I can shoot near cleans at 1000 in great weather, I know the load and the rifle are doing what they need to be doing.
 
Posts: 2650 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
Member
Picture of henryrifle
posted Hide Post
rduckwor - In the past two weeks I have incorporated an A&D FX120i into my hand loading routine. I use a Chargemaster to throw the charge, dump it into a pan on the A&D and adjust as necessary. It does add a step but it does not cost much time. By the time I have finished adjusting the charge and dumping it into the case, the next charge is ready. One bit of learning is that the Chargemaster is pretty good. I often find that I am adding or subtracting only a few granules of powder--I really mean 1-3 granules. There are some bad throws but the Chargemaster tells you that. Inserting the McDonald's straw in the Chargemaster really reduced the gross overthrows by 95% or more.

NikonUser - I am trapped in the technology world as that is my chosen profession. I have grown to view my mobile phone as a leash and have to fight a growing disdain for people (my wife and children included) sitting around together but fully engrossed in their tech to the exclusion of anything else.

Technology does have a place in reloading, however. I now put every shot group I make in Excel and can link those groups to the CSV that the Labradar produces. Not surprisingly, it is interesting what you find in Excel when sorting by MOA, velocity, case type or projectile.

The main reason I bought Quick Load was because H4350 is so hard to find that I wanted to see what else would work for the 6.5 Creedmoor and thought QL was a shortcut to buying several powders and putting in the meticulous work of developing loads.

As a non-competitor, I have since realized that a big part of the enjoyment of this sport is developing the load. If that were taken away then you'd just be manufacturing ammo and that is not that much fun. No matter how good the computer model, you still have to shoot it. As an aside, I have also learned that when you see a powder that is scarce just buy 20-30 pounds of it and stop worrying (for a long time).

I don't have quite the computer pedigree you have but close. I started in the mid '80s and was a Novell engineer in the early '90s. My background is Infrastructure and Operations and while I am a step or two removed from that today, I and my clients are still victims of bad implementations and poorly executed and tested shortcuts.

I will keep playing with Quick Load because it is interesting. I am not sure that I fully believe in Optimum Barrel Time but it appears to predict success in many (not all) examples and QL is the best tool I am aware of to further explore that correlation. Over time I am sure that I'll learn how to adjust QL to account for suppressor usage, magnum primers, neck tension and prone shooting Vs. bench shooting to name a few variables. Given the significant advances in chronograph technology over the past 5 years I wouldn't be surprised to see the ability to measure chamber pressure affordably come into the hand loading world. That would fill in a big piece of the puzzle.

Henryrifle
 
Posts: 442 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
Member
posted Hide Post
quote:
Originally posted by henryrifle:
Over time I am sure that I'll learn how to adjust QL to account for suppressor usage, .....and prone shooting Vs. bench shooting....

My TBAC Ultra 9 adds about 25 fps over bare muzzle for both 6.5 Creed and 308 Win loads. Quick and dirty, add one inch of barrel length for a suppressor for ballparking MV.

I've chrono'd the same gun with the same load on prone versus bench positions. No discernible difference in MV. MV shouldn't be any different for any position of a properly shouldered rifle. Now shoot a rifle free recoil, like some bench rest competitors do, and yes I'd expect a slightly lower MV. As in very slightly lower MV, and an MV difference that won't make or break a shooter's ability to hit a target until it's long ways out.
 
Posts: 4930 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
Member
Picture of henryrifle
posted Hide Post
Thank's fritz. I did Chrono my 6.5 with and without the TBAC Ultra 9 and there was no difference. I assumed that as the suppressor is a 30 cal that maybe the difference is measurable or greater for the .308. If there is a 25 fps difference, that would go a long way to helping me true QL to my barrel.

Thanks again,
Henryrifle
 
Posts: 442 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
Member
posted Hide Post
My Thunderbeast is a .308 can, so I can use it on both 6.5 and .308 rifles. I still see the MV increase on both 308 and 6.5 chamberings, for shooting with can, versus bare muzzle.

I verified increased suppressed MV from a magnetospeed v3 via down-range elevation requirements -- visually on steel targets at 600 to 1,000 yards.

I could not get suppressed MV data with from a Labradar unit. The Labradar's owner couldn't get the unit to pick up MV with my can attached, although the unit was good with bare muzzle and braked muzzle. After some 12-15 shots with no suppressed readings, and with his constant futzing with the unit, I said thanks but I'll go back to other methods.

I like the concept of the Labradar unit. Especially the futzing I have to do to put a Magnetospeed V3 on a suppressor. But that experience pretty much told me the Labradar won't be getting my money.

Using the revised & higher MV of my suppressed 6.5 Creed, JBM data tracked in ELR competition last month out to 1800 yards.
 
Posts: 4930 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
Member
Picture of henryrifle
posted Hide Post
Very easy to get suppressed data from Labradar. I NEVER miss a shot. Change the unit to trigger from Doppler. Make sure the unit is within 3 inches of the can--right beside it--not in front not behind but right beside it. Make sure the offset is set to 6 inches. When you double press the target button to arm the unit to record shots also press the settings button (small computer screen icon) to get rid of the ))) symbol which indicates that the Labradar is listening for the trigger. No futzing and no missed shots even with a guy shooting a 338 right next to you with a giant brake that bathes you in dust, warm air and ear ringing sound at each shot!
 
Posts: 442 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
Member
posted Hide Post
That's pretty much what the Labradar's owner did. He was explaining to me the procedures he used to obtain readings with other suppressed rifles. No dice on my suppressed rifle.

We were on the line of a dozen plus rifles, getting ready for a precision steel match. I had braked rifles on either side of me -- the Labradar unit wasn't picking them up.

The Labradar did pick up one reading of the 12-15 suppressed shots that was close -- just under 2800 fps. The others were no readings, readings in the 2500-2600 ballpark, and one well over 3500 IIRC. Whatever the reason, I was happy it was his money invested in the unit and not mine.
 
Posts: 4930 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
Member
Picture of henryrifle
posted Hide Post
Can't explain that but I own the exact same suppressor as you, shoot the same calibers and have no issues. The turning point was pressing the config button to make the Labradar stop listening with the mic and only trigger on doppler. I do use an external battery pack. I imagine your friend does too. They eat the batteries internal to the unit but I get days and days out of my pack and can charge my ballistics calculator -- I mean phone at the range.

Last thought. There are two kinds of failures when recording a shot. One is just no recording where you get nothing--no change to the screen and no data. The other is a message that you have to acknowledge where the Labradar got inconsistent or partial data. If you are getting no indication of a reading and no message, that is a configuration issue or a positioning error--either proximity to the barrel/suppressor or direction the Labradar is pointed. I do experience the second failure about 1 in every 50 shots or so. It usually occurs when I shift to a different target or have moved my mat and not properly repositioned the Labradar. This is very acceptable to me but others may disagree.

In any case the labradar is an all weather system that accurately captures a tremendous amount of muzzle velocity data as well as downrange data with no negative impact to POI. It may not be perfect but it is light years ahead of any other system and soon they will release an update and an app that will allow for remote control of the system. Can't wait for that. It is a pain in the ass to press all those buttons and scoot around the rifle to get there.

EDIT: I am just a customer and paid full price for my Labradar that I purchased from Midway. Reading the above one might conclude that I have a stake in the system and I do not. Just a very enthusiastic user and hate to see bad information about a good product. There are several Youtube reviews where Labradar is being trashed by people who either have not spent the time learning how to use the system or have no understanding of doppler radar. I am sure if you had one you would be getting the same good results that I am getting.
 
Posts: 442 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
Member
posted Hide Post
I was getting frustrated with my Magnetospeed -- it seemed to work only with brand new batteries and when I had the wand placed just perfectly.

Labradar was high on my buyer's list until I saw its performance first hand with an experienced shooter. He stated that alignment was an issue at first -- a problem solved by gluing a sighting tube into the notch on the top to the unit. He stated suppressors were an issue until he learned to put the unit right next to the can, then make the appropriate adjustments.

My frustration with Magnetospeed came from plugging in the cord to a port on the bottom and forward part of the unit. Offgrid's Magneto was plugged into the rearward-facing port, and it worked flawlessly. Hmmm -- I plugged into the rearward port with my Magneto, received readings within a foot or two of Offgrid's, and all was good. I do get a little POI shift from the Magneto, but in reality I'm more concerned with downrange, long distance, no futzing with other equipment, results.

Two consistent 5-round groups from a Magneto, pack the thing up, and I'm good to go with whatever position or location I want to shoot from.
 
Posts: 4930 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
Member
Picture of henryrifle
posted Hide Post
Not knocking Magnetospeed. It is a good system and if there was no Labradar, I would own one, however; it does introduce another variable to the equation and with Labradar that can be avoided completely. Not trying to argue an admittedly fine point; just justifying my choice.

Return to topic:

Zak over at TBAC confirms your point--that the Ultra 9 adds between 0 and 20 FPS to the MV.
 
Posts: 442 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
Knows too little
about too much
Picture of rduckwor
posted Hide Post
quote:
rduckwor - In the past two weeks I have incorporated an A&D FX120i into my hand loading routine.



Damn it!! I was afraid you were going to say that. I have so far resisted the purchase of the A&D scale and just continued to struggle with my Gem Pro 250. I see the light near the end of the tunnel.

RMD




TL Davis: “The Second Amendment is special, not because it protects guns, but because its violation signals a government with the intention to oppress its people…”
 
Posts: 18503 | Location: L.A. - Lower Alabama | Registered: April 06, 2008Reply With QuoteReport This Post
Member
posted Hide Post
quote:
Originally posted by rduckwor:
quote:
rduckwor - In the past two weeks I have incorporated an A&D FX120i into my hand loading routine.



Damn it!! I was afraid you were going to say that. I have so far resisted the purchase of the A&D scale and just continued to struggle with my Gem Pro 250. I see the light near the end of the tunnel.

RMD

Ha ha ha ha. Why resist it? You know you want one.

Sometime back, I replaced my Chargemaster with the AutoTrickler. I will be meeting Adam at the Worlds next month where I'm sure he will bring his new toys for sale.
 
Posts: 2650 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
Member
Picture of henryrifle
posted Hide Post
I have preordered Adam's AutoThrow/AutoTrickler. I am very much looking forward to seeing how that works. On average it takes me 45 seconds to throw a load with the Chargemaster, dump it into a container on the FX120i, adjust it and pour it into the case. If I can really cut that down to 20 seconds that would be awesome.
 
Posts: 442 | Location: Atlanta | Registered: November 11, 2009Reply With QuoteReport This Post
Member
posted Hide Post
I think you can reach that. I'm fairly close to that, give or take. The problem is doing a lot of repetitive, yet intricate operations very quickly. With age, it gets difficult sometimes.

This "getting old" is really getting old.
 
Posts: 2650 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
  Powered by Social Strata Page 1 2  
 

SIGforum.com    Main Page  Hop To Forum Categories  Reloading    Muzzle Velocity Question

© SIGforum 2017