Thread: Stupid Question. bare with me please

Newish reloader, have done alot of study and have had some success..Am reloading for 6.5 creedmoor Tikka T3x rifle, have been getting reloading data off XXL reloading am now looking at the New Hornardy 11th edition.. Am impressed by no.s however I am using Lapua brass and either wind river or federal primers the Lapua brass seems to be quite short 48.5 mil. I am looking at throwing the 147g Eld-m using Alliant 16/26. Hornardy manual says 71.12 mil COAL whereas I have been loading other ammunition to 70.1 mil ( 129 SST) I quess my question is, I don't know the Max cartridge length my rifle can handle, am I safe using the published COAL using different brass/primer as long as I start at the low end? and observe pressure signs ?!?!

Longer = less projectiles back into case= more case capacity which in turn = less pressure

Case overall length for your rifle will be determined by either your chamber or what will fit in your mag. A rough way I do it is size a case start to seat a projectile then I load it it my rifle and close the bolt on it remove round and that will give you your max chamber length, then you can see if the round fits in your mag. That's how I do it for all my rifles without special measuring gear.

Originally Posted by blip

Case overall length for your rifle will be determined by either your chamber or what will fit in your mag. A rough way I do it is size a case start to seat a projectile then I load it it my rifle and close the bolt on it remove round and that will give you your max chamber length, then you can see if the round fits in your mag. That's how I do it for all my rifles without special measuring gear.

This is pretty much how I do it too, although for reference this is but a functional check as I've never found a factory rifle that I've done this with where the resulting test round would fit in that rifle's magazine... Usually you have to seat to magazine depth. It's worthwhile doing this check so you know what the difference is between mag and throat length in my estimation. Doesn't really change much though?

Originally Posted by Pommy

10 thou back from being jammed into the rifling is a good way to get a pressure spike.

Why?

Factory ammo usually has a bigger jump than 10 thou? In real world as long as the developed pressure is under the limits of containment we never know about this, and in reality most often (unless it's a heavy pill or crimped) the primer gas is enough to start the pill moving towards the leade. From what I've looked at, the highest pressure situation is starting with the pill jammed into the lands or put another way there is no 'soft' movement of the bullet so the pressure curve sharply increases until the pill starts moving and being engraved by the rifling. The bigger the gap, the longer this process takes and the slower the pressure curve increases but the start of the bullet into the rifling is more abrupt - contact rifling, engraving happens and gone basically.

As noted - we usually don't notice this happening so it's purely theoretical for most of our interest here I think as long as the pressure remains under the limits of the components to contain it. If it's outside those limits then we notice it haha.

I'm saying that 10 thou is not far enough away from being jammed to aleviate the potential pressure spike from the bullet not having that run up. So we're in agreement, no?

Pressure won't be an issue if your following correct procedure and working up..... Regardless of seating depth.if your at staying load level you shouldn't get into trouble...yeah yeah if I took my nearly straight sided heavy for calibre and rammed it right down in case maybe...but normally not quite that silly

Originally Posted by Pommy

I'm saying that 10 thou is not far enough away from being jammed to aleviate the potential pressure spike from the bullet not having that run up. So we're in agreement, no?

Thanks, from your further explanation yep we are. I think that if you are careful in your load development, it doesn't matter where the pill is in relation to the lands - other factors can be more influential like tight carbon rings etc. I did read articles about load development where they do 'rough development' with the pill jammed and once at the velocity and basic group they want they then tune the load by adjusting seating depth deeper. In most cases this seems to slightly lower the pressure and adjust the harmonics. I find as we mentioned earlier that this is kinda a BS way to go for the average factory rifle - nice academic argument but in reality if the round won't fit in the mag it is really not much use for the majority of people's hunting use. Mental note - must try those subs again (my .308 sub load uses the 175gr Sub-X pill seated to cannelure, which has most of the pill in the case taking up volume and about a 6Km jump to the lands for 3-shots touching at 50m).

You should be fine using Hornadys published coal for that projectile.

That said there are several ways to determine max coal for your rifle/bullet combination without having to purchase specialist equipment.
I use my cleaning rod and a bit of tape (youtube it) I've also used a fired case that's been resized and then cut a slot in the neck, again youtube it.
Locktite and a fired case is another method.

Alternatively you can load to your shorter coal and start at published minimum load and work up.

IMHO it is very useful to learn how to find the lands and then work out your bullet jump, it will expand your understanding of reloading.

To my mind this is exactly what forums are for. Ask away mate. better to be safe.

First question is what twist barrel have you got? The 147 is a heavy pill and likely needs an 8 twist.

If you are new to reloading I would not get too hung up on trimming cases. I personally never trim but I do use an M die. I have never had an issue with case necks hitting the back of the throat. I know they grow over time and if you don't use an M Die you may have inconsistent neck tension. For now I wouldn't worry about it. 90% of the crap we do makes little difference. The spec is 48.771mm

As for the COAL I generally ignore that altogether. In a factory hunting rifle the throat is generally long unless its a Howa. I have done loads for 2 of those recently and they were bloody good! Rem 700 are long. I seat a projectile progressively till it jams slightly in the lan's then set them back 10thou. Then check they fit your mag.

Run your powder up till it settles to a low ES on your chrony then adjust your seating depth to adjust your group size 3-5 thou steps. I only ever shoot 3 shot groups during this process. Without a crony you are flying blind and this system will not work well. EDIT: Powder selection is pretty critical! If you are reading this and think you can apply this to your loads and do as I say here you will get into trouble. I determine all my loads in QL before I do this. It has never failed me! Not once!!

I thinking you may have to stick with your 129 SST load.

if so a starting recommendation would be 129SST with 44grains of Reloader 17 and that will be somewhere close to max pressure. My experience with QL is you will find your ES will level out about 2% above that. If you feel more comfortable starting lower then by all means do so, but you will find primers wont start showing pressure till you are in the red zone. That said pressure shows up differently in every gun so if you are not sure what you are doing I would not recommend you go above the 44 Grains I have suggested here.

I hope this helps and keep me posted how you get on.

Edit I couldn't post QL data. Seriously questioning the wisdom of posting this. Its all easy in my head as I type it and happy to help but then you think of the wider implications and maybe this is not smart. Lets see how it goes. If I get flamed I'm out.

Originally Posted by Taranaki Shooter

To my mind this is exactly what forums are for. Ask away mate. better to be safe.

First question is what twist barrel have you got? The 147 is a heavy pill and likely needs an 8 twist.

If you are new to reloading I would not get too hung up on trimming cases. I personally never trim but I do use an M die. I have never had an issue with case necks hitting the back of the throat. I know they grow over time and if you don't use an M Die you may have inconsistent neck tension. For now I wouldn't worry about it. 90% of the crap we do makes little difference. The spec is 48.771mm

As for the COAL I generally ignore that altogether. In a factory hunting rifle the throat is generally long unless its a Howa. I have done loads for 2 of those recently and they were bloody good! Rem 700 are long. I seat a projectile progressively till it jams slightly in the lan's then set them back 10thou. Then check they fit your mag.

Run your powder up till it settles to a low ES on your chrony then adjust your seating depth to adjust your group size 3-5 thou steps. I only ever shoot 3 shot groups during this process. Without a crony you are flying blind and this system will not work well. EDIT: Powder selection is pretty critical! If you are reading this and think you can apply this to your loads and do as I say here you will get into trouble. I determine all my loads in QL before I do this. It has never failed me! Not once!!

I thinking you may have to stick with your 129 SST load.

if so a starting recommendation would be 129SST with 44grains of Reloader 17 and that will be somewhere close to max pressure. My experience with QL is you will find your ES will level out about 2% above that. If you feel more comfortable starting lower then by all means do so, but you will find primers wont start showing pressure till you are in the red zone. That said pressure shows up differently in every gun so if you are not sure what you are doing I would not recommend you go above the 44 Grains I have suggested here.

I hope this helps and keep me posted how you get on.

Edit I couldn't post QL data. Seriously questioning the wisdom of posting this. Its all easy in my head as I type it and happy to help but then you think of the wider implications and maybe this is not smart. Lets see how it goes. If I get flamed I'm out.

Standard twist rate for 6.5 Creedmoor is 1:8 so the 147 will be fine.

The Lyman M die is not necessary to get consistent neck tension. A standard set of reloading dies is fine.

10 thou back from being jammed into the rifling is a good way to get a pressure spike.

Needs a lot of rounds to give a good enough sample size to say with any certainty that a particular charge is giving a better ES than another. 3 rounds is not nearly enough. It probably won't make any meaningful difference. Same goes for grouping.

Adjusting seating depth is also not likely to make any noticeable difference with that bullet in a Creedmoor chamber.

Recommending that they START with what you think is a MAXIMUM load... of what is also an expensive and hard to get powder???

Originally Posted by Pommy

Standard twist rate for 6.5 Creedmoor is 1:8 so the 147 will be fine.

The Lyman M die is not necessary to get consistent neck tension. A standard set of reloading dies is fine.

10 thou back from being jammed into the rifling is a good way to get a pressure spike.

Needs a lot of rounds to give a good enough sample size to say with any certainty that a particular charge is giving a better ES than another. 3 rounds is not nearly enough. It probably won't make any meaningful difference. Same goes for grouping.

Adjusting seating depth is also not likely to make any noticeable difference with that bullet in a Creedmoor chamber.

Recommending that they START with what you think is a MAXIMUM load... of what is also an expensive and hard to get powder???

This is the problem with a forum.

I have been loading and developing loads for years for both competition and long range with pretty good success. I have used QL for at least 15 years. That's how I do it and never had a problem. My goal is to build the highest preforming ammo I can. I would have thought that was why we all reload.

QL is extremely good at identifying the most efficient powder for a particular cartridge and projectile. I look for a powder that fills the case to 100% burns 100% with a high efficiency. In that case RL17 was the winner. There are several other powders that come close so if cheap is what you a looking for by all means use it. That said a 6.5 Creedmore is no super long-range cartridge so maybe having your ES under 10 is not a big deal.

I'm not sure why you are all hung up on firing 5 shot groups when developing a load. It makes no sense to me at all. If you know how to read a group 3 is plenty. In my own gun I never bother with much more and nor have any other top shooters I know. That said a factory rifle more often than not will open up after 3 shots. If you are stalking with it who cares what happens after 3 shots. If you run full custom guns like me I have no doubt your experience is the same as mine, they will put 10 through the same hole. For the record I do test my finial load with a 10 shot more than anything to see when the barrel start fouling a bit.

44 was not max pressure but near to. On every single load I have developed over the years the ES settles a bit above max pressure assuming you are using the correct powder.

I get that if you have no experience with QL it seems a very foreign way to go about load development but once you understand what you are doing its an extremely reliable tool. It will predict velocities to with in 20fps or much better.

It is clear to me that you have not understood the method I was suggesting and so that is ultimately my fault as I really did need to write a book to join the dots. I am not going to bother responding to all of it as much of it has already been proven over and over not to be true.

I know my effort here is futile and I will ultimately get shouted down and that is unfortunate. This is really a hunters forum and sticking to basic loads is ultimately the best advice. It certainly keeps things safe at the expense of stifling discussion.

I will respectfully leave it at that.

Originally Posted by Taranaki Shooter

I know my effort here is futile and I will ultimately get shouted down and that is unfortunate.

Not at all. If you're willing to have a good discussion using data to try to arrive at the right answer, rather than to prove that you are right, it's more than welcome.

Process I now use, & works well https://www.youtube.com/watch?v=Zglr3m5v-nI

Originally Posted by Mroach

Newish reloader, have done alot of study and have had some success..Am reloading for 6.5 creedmoor Tikka T3x rifle, have been getting reloading data off XXL reloading am now looking at the New Hornardy 11th edition.. Am impressed by no.s however I am using Lapua brass and either wind river or federal primers the Lapua brass seems to be quite short 48.5 mil. I am looking at throwing the 147g Eld-m using Alliant 16/26. Hornardy manual says 71.12 mil COAL whereas I have been loading other ammunition to 70.1 mil ( 129 SST) I quess my question is, I don't know the Max cartridge length my rifle can handle, am I safe using the published COAL using different brass/primer as long as I start at the low end? and observe pressure signs ?!?!

Different bullets have different profiles which results in manufacturers giving them different suggested COAL's. The suggested COAL for the bullet should give it plenty of jump in any SAAMI/CIP specification chamber. So in answer to that question, yes, you are absolutely safe to use the published COAL. The brand of brass and primer that you choose to use has no bearing on this.

As a side, I would ignore whatever XXL reloading is and just stick to the Hornady and Hodgdon data. Reloder 16 can give a little more speed over AR2209/H4350 but not enough to justify the extra cost IMO. Reloder 26 can give even more speed but there are drawbacks to using it in 6.5 Creedmoor. In order to get the extra speed you end up with quite heavily compressed loads and it can be a bit erratic.

I suggest keeping it simple. Stick with AR2209 and stick with the published COAL unless you are going to measure things properly. Do your workup from somewhere safely away from max charge and stop before you exceed the maximum speeds that the data suggests you should top out at (assuming you have the same length barrel, if not adjust your expectations down accordingly).

Not a stupid question at all but for some reason I thought of this