Case trim .308 Win
- Thread starter 308Loader
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Nice, 700P is an accurate rifle for sure but it is not a bench rifle. BartB once posted that you may see 1/20th of an inch improvement if you keep all your brass at the exact same OAL.
I shoot a Savage Precision Carbine, my son a R700 MilSpec and we can't tell any difference regardless of if I'm using brass I trimmed or brass that all were under spec.
I shoot a Savage Precision Carbine, my son a R700 MilSpec and we can't tell any difference regardless of if I'm using brass I trimmed or brass that all were under spec.
Only with the methods and techniques. I understand the resistance to change shared by reloaders. measuring the length of the case can/could be faster and trimming a case to length for a chamber a reloader does not have could result in longer cases.
I have a chamber that allows for cases that are longer from the mouth of the case to the case head by .016", I could trim to match 'trim to' case length but that would result in a case that does not cover my chamber. And, that is what I want, I want a case to cover all of the chamber.
F. Guffey
From what I've ben reading on this forum I seem to see a pattern in your answers guffey. It seems to be mostly about measuring ones particular chamber from bolt face to lands and everything in between. Would a chamber casting be a good way to measure all of it? Not to be sarcastic, but my calipers don't fit in my chamber. I Have a lot to learn yet, and I appreciate all the info this forum provides to new loaders like myself.
4runnerman
New member
I trim every loading. Everything the same length, everything consistant, everything same as last time I loaded. Get the same results each time to the range. anneal every 4th load. You want to be consistant every load. Same shoulder bump,same neck tension, same seating depth.You find a load that shoots great in your rifle-Keep loading that load exact every time. Just makes sense.
Now if Bart chimes in ( smart guy). he will talk about throat erosion, which I have no doubt is real. I have well over 3000 rounds down my match 308 rifle and to this day, still seat every load the same as I did 2 years ago and still get same results on target. If the day comes that my groups start to get out of control , a new barrel will be ordered. And then the game starts all over to find the perfect load.
I have 9 rifles now and I have one load for each of them. I do not mess with 2 or 3 different loads for each rifle. One load per rifle. Same bullet, trim length,primer,powder and seating depth.
Now if Bart chimes in ( smart guy). he will talk about throat erosion, which I have no doubt is real. I have well over 3000 rounds down my match 308 rifle and to this day, still seat every load the same as I did 2 years ago and still get same results on target. If the day comes that my groups start to get out of control , a new barrel will be ordered. And then the game starts all over to find the perfect load.
I have 9 rifles now and I have one load for each of them. I do not mess with 2 or 3 different loads for each rifle. One load per rifle. Same bullet, trim length,primer,powder and seating depth.
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Thank you,
I use the same type dial calipers as you, when determining the length of a 308 W chamber from the shoulder to the bolt face or the beginning of the chamber throat to the bolt face I form transfers, the transfers allow me to move the dimensions of the chamber to a comparator or gage.
Chamber casting? I do not find it necessary to case a chamber, again, I form cases, the 308 W chamber is shorter than the 30/06 chamber from the shoulder to the bolt face by .388". With .388" I can not miss.
I make chamber castings, there is a lot of work involved and different.
F. Guffey
Then there is changing the attitude of reloaders, there are modifications that can be made to adept tools for other purposes. That is not easy to talk about on a reloading forum, I am of the opinion reloaders are investors in companies that are manufacturers of reloading equipment.
There are at least three ways to determine the length of a chamber without a head space gage.
F. Guffey
There are at least three ways to determine the length of a chamber without a head space gage.
F. Guffey
0.01" of case neck isn't going to make any practical difference supporting the bullet.
The reason for trimming cases is to keep them from extending into the part of the bore where there is no clearance for the case to expand and release the bullet (which creates high, possibly dangerous pressure).
The only other reason to trim brass is for uniformity. And that only matters really matters when crimping.
If you are trimming after every firing, I think you are overdoing it.
The reason for trimming cases is to keep them from extending into the part of the bore where there is no clearance for the case to expand and release the bullet (which creates high, possibly dangerous pressure).
The only other reason to trim brass is for uniformity. And that only matters really matters when crimping.
If you are trimming after every firing, I think you are overdoing it.
This is kind of a long winded story to get to a point...
I once saw a youtube video of a guy sporting custom thousand dollar rifles, checking the bores with an 800 dollar bore scope with video attachment, showing his Dillon reloading presses.
I was impressed until he took his handloads to the range, ran them through his thousand dollar rifles, and came back with 5 moa groups.... He was convinced he was a great hand loader and shooter, but I remain skeptical.
So if you are trimming every reload, and it's working for you, by all means stick with it. If you stop trimming every time I expect you won't see a difference with a 700P, but sometimes having a ritual for reloading does more for the trigger nut than anything else.
Jimro
I once saw a youtube video of a guy sporting custom thousand dollar rifles, checking the bores with an 800 dollar bore scope with video attachment, showing his Dillon reloading presses.
I was impressed until he took his handloads to the range, ran them through his thousand dollar rifles, and came back with 5 moa groups.... He was convinced he was a great hand loader and shooter, but I remain skeptical.
So if you are trimming every reload, and it's working for you, by all means stick with it. If you stop trimming every time I expect you won't see a difference with a 700P, but sometimes having a ritual for reloading does more for the trigger nut than anything else.
Jimro
4runnerman
New member
Trimming everytime is probebly not a requierment, but it does keep everything the same from shot to shot. 44AMp- It has nothing to do with bullet hold or support. It has to do with each bullet being the same as the last. Does it make a difference- According to you-no, but then thats according to you. Each to there own I guess. I like to know when I dont hit the bullseye- It was operator error that caused it.
The top Bench shooters I talk to do it, they also anneal every round. They do this for a reason. They have found out IT does make a difference. I do not aspire to be a good shooter I want to be a great shooter, and that is why I do it.
I shoot about 300 to 500 rounds a week and continue to get better and better. I put my faith in what the top shooters do over what You and I and a few others think.
I became a member of this forum for 1 reason that has turned into 2 reasons. First was to learn from all the great members in here and second to help others with what I can. Through the years now my posts have changed from what I thought I knew to what I know now. I have now Had Bart on an occasion have people private e mail me for info and advice also. I take that as a very large compliment. In the end- I am here for the same reason you are-To learn and teach. I tell things that have taken me from a MOA shooter to a sub MOA shooter. While 70% of my shooting is 300 yards I still get out once a month and stretch it to 1000 to 1400 yards.
The top Bench shooters I talk to do it, they also anneal every round. They do this for a reason. They have found out IT does make a difference. I do not aspire to be a good shooter I want to be a great shooter, and that is why I do it.
I shoot about 300 to 500 rounds a week and continue to get better and better. I put my faith in what the top shooters do over what You and I and a few others think.
I became a member of this forum for 1 reason that has turned into 2 reasons. First was to learn from all the great members in here and second to help others with what I can. Through the years now my posts have changed from what I thought I knew to what I know now. I have now Had Bart on an occasion have people private e mail me for info and advice also. I take that as a very large compliment. In the end- I am here for the same reason you are-To learn and teach. I tell things that have taken me from a MOA shooter to a sub MOA shooter. While 70% of my shooting is 300 yards I still get out once a month and stretch it to 1000 to 1400 yards.
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If you would get off of the "repeat after me" and refrain from 'siding' you could determine throat erosion with tools that were designed for other purposes. I have a tapper/inline/butt grinder. It is not a matter of making gages, it is about determining the distance to the lands, a reloader that has no clue what the distance was when the rifle was chambered is left with using a bore scope and or making a chamber cast.
F. Guffey
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4runnerman
New member
Guffy- I also said I have NO DOUBT it's true- However so far in 3000 plus rounds it has not made a difference on my accuracy that i get from the rifle.
I still seat to the same depth as I did when the rifle was new. I also do not worry nor care about throat erosion, as when the groups open up-I buy a new barrel. I buy one a year for my 6BR. I find one load that shoots great and that is what I shoot always. Barrels are a expendable item. I have never found a need for all the gauges you have. I have the Hornady gauge to measure my seating depth to the lands and that is all I need. I do not need to measure throat erosion- I buy a new barrel. Don't need 90% of the tools you have Guffy.
I load , I shoot, I load , I shoot, when things go South-I buy a new Barrel and go back to loading and shooting. You seem to have tool for everything- What has it gained you?. Answer-Nothing other than Money and the ability to measure a shot barrel. Heck I do that for free just by watching my groups.
Got well over 15,000 rounds down my 223-Still shooting the same bullet,same powder, same AOL I started with 5 years ago. Still pulling the same accuracy. Do I have throat erosion-Yes. Has it made a difference-NO.
With all your tools and stuff you do Guffy- Do you even have time to shoot any more?.
I bet you have a tool to measure everything.
I still seat to the same depth as I did when the rifle was new. I also do not worry nor care about throat erosion, as when the groups open up-I buy a new barrel. I buy one a year for my 6BR. I find one load that shoots great and that is what I shoot always. Barrels are a expendable item. I have never found a need for all the gauges you have. I have the Hornady gauge to measure my seating depth to the lands and that is all I need. I do not need to measure throat erosion- I buy a new barrel. Don't need 90% of the tools you have Guffy.
I load , I shoot, I load , I shoot, when things go South-I buy a new Barrel and go back to loading and shooting. You seem to have tool for everything- What has it gained you?. Answer-Nothing other than Money and the ability to measure a shot barrel. Heck I do that for free just by watching my groups.
Got well over 15,000 rounds down my 223-Still shooting the same bullet,same powder, same AOL I started with 5 years ago. Still pulling the same accuracy. Do I have throat erosion-Yes. Has it made a difference-NO.
With all your tools and stuff you do Guffy- Do you even have time to shoot any more?.
I bet you have a tool to measure everything.
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)...Back to the beginning, it has something to do with trimming case length. I am the only reloader that makes gages for determining the length of a chamber from the throat to the bolt face. It seems everyone else uses a reloading manual, again 'seems' they have 'trim to length' or maximum case length according to SAAMI.
Then there are design functions of tools used by reloaders. Most reloaders measure the length of a case from the end of the neck to the case head.
F. Guffey
4runnerman
New member
Guffy- Case length is a given. Shoulder bump is what is important. Which again-You do not need a tool to determine