Starting weight for load development please?

[Paul]

Hi all,

Wanting to develop a load for a new 22-250 (Tikka T3x).
Ive searched EGun forum, and not gotten a clear answer. Searched YouTube, same outcome. So here I am asking you folks for help once again

There seems to be a few ideas of where to start a load, much less on where to stop - pretty much unanimous in when you get pressure signs.

Some options I have seen include:

* Start at the minimum for that powder and go up in 0.2gr increments.
* Start at 10% below minimum and go up in 0.5gr inc. (for 2206H this gives 13 possible loads to maximum!!!)
* Start 7% below maximum and work up.
* Start 1/3 the way up from min to max, and increase by increments of 1% of maximum load e.g. 1% x 35.5 = 0.355gr. (I have tried this method, works OK, but misses the lighter end of the load range).

So I'm a bit lost and wondering what you guys do? I'm keen to explore the bottom end, even just under minimum coz in my old rifle, I got good results from a load suggested to me that was 1gr under min, when none of my try outs were anywhere near that light.

Over to yous

Paul

[LawrenceA]

Minimums are potentially as critical as the maximum if not more so.
Going below minimum may lead to a phenomenon called detonation. They think it is when the powder fizzes then ignites in a pressurized case or the fizz propels the remaining powder against the base of the bullet that acts like an obstruction. Either way the gun does more then go bang.
Further generally speaking a powder close to full capacity will ignite and burn more consistently than a faster lesser load.
However My 6.5 Tikka shoots best with the fastest powder and I mean 0.2 moa vs 1.0 moa.
Basically I would start at minimum and work up in probably 1 or even 2 grain increments (work out the range and divide by 5) then re test once you determine the points at which the group stops shrinking and starts expanding.
2206H is a different beast as you can start at 50% versus 60 or 70% capacity.

[in2anity]

You are way over complicating it. Start on the minimum listed load (http://www.adi-powders.com.au/rifle/22-250-remington/ ) for that weight projectile (or as close as possible), and work your way up to listed maximum, looking for pressure signs particularly when you get near the top end (which will be unlikely in a modern action). It’s not rocket science. Personally I don’t think 0.1gr increment means diddly squat. 0.3gr increment is fine probably even 0.5gr to start with. You need a very big sample size of data to be concluding hyper specificity.

[Oldbloke]

Deleted

[Oldbloke]

I would just refer to the ADI manual on line.
Select bullet weight and powder.
Start at minimum and work up in .3 or .5 grains. 0.2 is getting a bit too tedious.
Having said that after finding a good load working up 0.5 gr you could go back and try 0.2 above and below that load to fine tune if you want.

Suggest you seat the bullet about 0.20" off the lands.

[LawrenceA]

Minimums are potentially as critical as the maximum if not more so.
Going below maximum Typo should say minimum may lead to a phenomenon called detonation. They think it is when the powder fizzes then ignites in a pressurized case or the fizz propels the remaining powder against the base of the bullet that acts like an obstruction. Either way the gun does more then go bang.
.

Thanks mate yes I do mean minimum

[bladeracer]

Minimums are potentially as critical as the maximum if not more so.
Going below minimum may lead to a phenomenon called detonation. They think it is when the powder fizzes then ignites in a pressurized case or the fizz propels the remaining powder against the base of the bullet that acts like an obstruction. Either way the gun does more then go bang.
Further generally speaking a powder close to full capacity will ignite and burn more consistently than a faster lesser load.
However My 6.5 Tikka shoots best with the fastest powder and I mean 0.2 moa vs 1.0 moa.
Basically I would start at minimum and work up in probably 1 or even 2 grain increments (work out the range and divide by 5) then re test once you determine the points at which the group stops shrinking and starts expanding.
2206H is a different beast as you can start at 50% versus 60 or 70% capacity.

Very few load data list minimums, they just list starting loads, you can go lower. If they don't want you to reduce it they will include a warning.

[boingk]

Start minimum, go half grain increments until you're 1gn from max. If max is compressed stop 1.5gn from it.

Now go in 0.25 increments until you're half a grain from max or thereabouts.

Now go 0.1 and see where it takes you.

Be careful and deliberate and mark all loads properly - whatever works for you. I like strips of paper in the load box with the grain amount written on for each column of five rounds. Can't miss it then.

Cheers - boingk

[Oldbloke]

Bladeracer is correct. Correct term is starting load. But until you know what your doing i recommend you keep loads between start and max load.

[Oldbloke]

All good Lawrence.

It was easier to just fix it.

[LawrenceA]

All good Lawrence.

It was easier to just fix it.

Yeah did that to.

[Oldbloke]

Off another forum. I would consider this an overload.

[boingk]

For someone who may not know what they're looking at with that picture, the dead-flush-and-filled primer pocket coupled with the slightly cratered firing pin indent is a good indication its overloaded.

That round may or may not have also had a hard extraction - you would likely feel something different if extracting a round similar to the above, a sticky/hard bolt turn or hard pull to the rear for example. You also may not.

[Col]

Off another forum. I would consider this an overload.

Oldbloke this is a very useful photo, especially for those starting out, as it shows overpressure signs really well. Thank you for posting.

Col

[Oldbloke]

Here's one off the net. I consider this normal.

Screenshot_20210218-224710_DuckDuckGo.jpg (501.65 KiB) Viewed 7105 times

[straightshooter]

For someone who may not know what they're looking at with that picture, the dead-flush-and-filled primer pocket coupled with the slightly cratered firing pin indent is a good indication its overloaded.

That round may or may not have also had a hard extraction - you would likely feel something different if extracting a round similar to the above, a sticky/hard bolt turn or hard pull to the rear for example. You also may not.

It could also be due to a case with excessive headspace.
The only reliable way to know would have been to accurately measure case head diameter before and after firing.

[Paul]

Thanks for all the post so far. Yes, my mistake, I actually meant 'starting' load, as stated in most powder manuals. I'm aware of the issues with loads that are too light and issues with 'funky' ignition.

I still get the sense that there is a leaning towards seeking loads at the upper end of the range. No thoughts on going under the 'starting' load?

Kind regards,

Paul

[Oldbloke]

Both out of the 9th ed ADI manual.

Reduced loads 60% max 2206H.JPG (72.59 KiB) Viewed 7070 times

Reduced loads 75% of Case capacity.JPG (39.94 KiB) Viewed 7070 times

And this

Explosive detonation.jpeg (38.52 KiB) Viewed 7070 times

[on_one_wheel]

No thoughts on going under the 'starting' load?
Kind regards,

Paul

I don't see any value in starting under, besides the previously mentioned safety factor, even if still safe it's a waste of time and powder.
In most cases, the objective of hand loading is to find a recipe that gives you the fastest possible combination without showing over pressure signs, the faster speed within an accuracy node will give you the best performance from your projectile, shoot flatter, be less affected by wind.

Hopefully you've got your hands on a reloading book like one of Nick Harvey's.
They are priceless when starting out.

[Oldbloke]

Did someone mention Reloading Manuals.

http://marvinstuart.com/firearm/Manuals ... 20Manuals/



https://www.rcbs.com/rcbs-how-to-reload ... ading.html

[in2anity]

I don't see any value in starting under, besides the previously mentioned safety factor, even if still safe it's a waste of time and powder.
In most cases, the objective of hand loading is to find a recipe that gives you the fastest possible combination without showing over pressure signs, the faster speed within an accuracy node will give you the best performance from your projectile, shoot flatter, be less affected by wind.

Hopefully you've got your hands on a reloading book like one of Nick Harvey's.
They are priceless when starting out.

We are not all from the F-brigade. I shoot Service Rifle, and 303 was my caliber last season. A big factor for me is managing felt recoil. Of course it's a tradeoff between recoil, accuracy and economy. Hence a faster powder like AR2206H, not fully filling the case was my personal choice. It'll still shoot Vs from the prone line, if you're doing your part, don't you worry about that. Bugger subjecting yourself to fullbore-type recoil out of a service rifle (if it can be avoided), when distances are generally under 500m. Most guys tend to go slightly slower than AR2206H (AR2208), but yeah a full case of AR2209 out of service rifle is a well known punisher.

[Tilb004]

Hi all,

Wanting to develop a load for a new 22-250 (Tikka T3x).
Ive searched EGun forum, and not gotten a clear answer. Searched YouTube, same outcome. So here I am asking you folks for help once again

There seems to be a few ideas of where to start a load, much less on where to stop - pretty much unanimous in when you get pressure signs.

Some options I have seen include:

* Start at the minimum for that powder and go up in 0.2gr increments.
* Start at 10% below minimum and go up in 0.5gr inc. (for 2206H this gives 13 possible loads to maximum!!!)
* Start 7% below maximum and work up.
* Start 1/3 the way up from min to max, and increase by increments of 1% of maximum load e.g. 1% x 35.5 = 0.355gr. (I have tried this method, works OK, but misses the lighter end of the load range).

So I'm a bit lost and wondering what you guys do? I'm keen to explore the bottom end, even just under minimum coz in my old rifle, I got good results from a load suggested to me that was 1gr under min, when none of my try outs were anywhere near that light.

Over to yous

Paul

Hi Paul

I have tikka 22-250 tx3 as well .
I shoot 55 gr v- max , 36.5 gr of 2208 and cci
Large primers .
I estimate around 3700 to 3800 FPS.
Has been very accurate and no pressure signs on primers or bolt hard to open .
I might try to up it a bit more .
Also have some data for trailboss powder.
That’s good fun shooting rabbits, 35 and 40 gr bullets doing around the 2000 fps heaps quieter if your interested .
Regards
Wayne

[bladeracer]

Thanks for all the post so far. Yes, my mistake, I actually meant 'starting' load, as stated in most powder manuals. I'm aware of the issues with loads that are too light and issues with 'funky' ignition.

I still get the sense that there is a leaning towards seeking loads at the upper end of the range. No thoughts on going under the 'starting' load?

Kind regards,

Paul

The "max" load is only what they found in their testing with their rifle (and often taken from computer modeling with no actual load testing), it is unlikely to be a max load in your rifle as well. Depending on how you load, and the dimensions of your chamber and throat, will determine where your maximum load is. FLS'ed brass gives greater pressure than brass already formed to fit the chamber. If you seat the bullet longer than specified you will have less pressure and can probably go well over somebody else's maximum, unless your bullet is seated so long as to touch the rifling, then you will have very high pressure. If you seat the bullet deeper you will also see higher pressures.

If you are chasing velocity for some reason, then you will have to keep going until you find the pressure signs yourself, to know where your maximum is. For me, I don't load anywhere close to seeing pressure signs, even when well above published data. If I need a bigger bang then I use a different chambering or I learn to get closer to my targets. I carry "enough gun" for the possibility of larger targets or longer distances, but most of the time the targets are _much_ closer, so I don't need a 4400fps load when a 2400fps one easily does the job, with significantly less recoil, blast, cost, throat erosion, and wear and tear on my neighbours and myself. I keep some full-noise loads handy in case a long-range shot becomes necessary, but the rifle is loaded with reduced loads.

Greatly reduced loads are only dangerous under quite specific situations, very small charges of very slow powders in very large cases _may_ result in SSE, or Secondary Explosion Effect, but even test labs have trouble reliably replicating it deliberately. Its randomness is the best reason to avoid the situation entirely if possible. Faster powders in smaller cases are rarely a problem.

So, to answer your question directly, if I want a low-pressure load but still with some energy, I would start around the start load, then work up or down until you find what suits you best. Because pressure builds faster as you increase the charge (as you use more powder you also reduce case volume), starting loads are generally fairly light to begin with. In a 40gn start to 46gn max spread, going from 40gn to 41gn makes little pressure increase compared to going from 45.5gn to 46gn.

[wanneroo]

I've seen reloaders ask this, especially new reloaders and they are looking for a specific formula to follow starting a load. I don't believe there is one. All depends on the cartridge and it's quirks, what bullet you are using, what powder and perhaps even what primer. And then plus you have to take into account the firearm itself and it's quirks.

This is why I believe it's a good idea to have multiple manuals plus online materials. So I take in account all the above factors, research it and then reach a consensus on what I think will be my starting load.

The other thing is you need data to compare with the written materials you have researched, so I recommend you verify your data with a chronograph when testing your loads. Recently I bought a Magnetospeed which attaches to the barrel of the rifle and is very compact and easy to use compared to setting up a traditional chrono.

[bladeracer]

I've seen reloaders ask this, especially new reloaders and they are looking for a specific formula to follow starting a load. I don't believe there is one. All depends on the cartridge and it's quirks, what bullet you are using, what powder and perhaps even what primer. And then plus you have to take into account the firearm itself and it's quirks.

This is why I believe it's a good idea to have multiple manuals plus online materials. So I take in account all the above factors, research it and then reach a consensus on what I think will be my starting load.

The other thing is you need data to compare with the written materials you have researched, so I recommend you verify your data with a chronograph when testing your loads. Recently I bought a Magnetospeed which attaches to the barrel of the rifle and is very compact and easy to use compared to setting up a traditional chrono.

I don't consider a chronograph essential, but it can give you useful data. The velocities listed with load data are also individual to the specific test setup.

It takes less effort to "set up" my chronographs than it would take you to strap yours on, I stand it on the tripod (it stays attached to a tripod) in front of my rifle, switch it on, and start shooting, it's very, very quick and easy to use.

Does the Magnetospeed work on semi-auto handguns?

[on_one_wheel]

I reloaded for years without a chrony.

I only bought one to accurately measure velocity when I started plinking beyond 500 meters.
I needed data to plug into a ballistic calculator.

[bladeracer]

I've seen reloaders ask this, especially new reloaders and they are looking for a specific formula to follow starting a load. I don't believe there is one. All depends on the cartridge and it's quirks, what bullet you are using, what powder and perhaps even what primer. And then plus you have to take into account the firearm itself and it's quirks.

This concept can take a while to come to terms with, that there are no hard or fast rules on the results of the cocktail you build.
We start with very rigid constraints, 55gn bullet, 2800fps, 26.5gn of powder and so on, but the result we see is not fixed as a result.
I liken it more to setting the shower temperature, it's a matter of feel rather than something that can be precisely quantified.
In the end it's only the result that matters, how we achieve it is really only relevant so that we can try to achieve it again next time as well.

[wanneroo]

I don't consider a chronograph essential, but it can give you useful data. The velocities listed with load data are also individual to the specific test setup.

It takes less effort to "set up" my chronographs than it would take you to strap yours on, I stand it on the tripod (it stays attached to a tripod) in front of my rifle, switch it on, and start shooting, it's very, very quick and easy to use.

Does the Magnetospeed work on semi-auto handguns?

I reloaded for a few years without the chrono, but I found it to be a useful data point to show where you are with velocity just as rounds hitting the paper show you where you are with accuracy in the conditions you are in, all human induced factors aside. I understand that velocities listed with load data are specific to that test set up and I take that into account when looking at all load data.

No the Magnetospeed doesn't work with semi auto handguns. I find it light, compact and easy to use. Also works for my range so I can do accuracy testing at the same time when shooting rifle. I don't have a flat range due to the mountain, except for the first 30 yards that got bulldozed out for pistol.

At some point I might get one of those fancy Labradar chronos.

I'm going to do a review of the Magnetospeed on my Youtube channel when the weather improves. Right now I have to snow shoe in to the range, it's snowmageddon and everything is locked in ice.

[bladeracer]

At some point I might get one of those fancy Labradar chronos.

Why?
Just use a $250 ProChrono, it does everything most people need from a chronograph.

[on_one_wheel]

I bought myself a Candaian made Shooting Chrony because screw you china

Unfortunately I'm lead to believe their out of business.