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I've measured my 6.5x55 chamber


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I've just borrowed a gauge to measure the size of the chamber on my 6.5x55. With Speer 140grn softpoints it's measuring 3.170. I know I shoud back the bullet off the lands a little for pressure reasons, but how much? My Lee book says min OAL is 3.030 with Varget, but to have the bullet too far from the lands is bad? I can't for the life of me find where it says how much to back it off once measured, but I'm sure it did say somewhere when I read the whole book.

 

How do you guys go about it? I'm really stuck on this :rolleyes:

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I don't know about a 6.5 but when they started using 155gr bullets in 7.62 you had to have your rifles checked to ensure the bullet was not tight in the lands.

 

If it was then you could only use the 144gr bullet which is slightly shorter.

 

Surely the bullet does not effect the chamber langth as that is fixed, it will be OAL of the round you need to ensure is correct.

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Fair enough. I'll give it a try at the minimum length then. Nosler 120grn ballistic tips seated to 3.000 are the best homeloads so far so it's worth a go.

 

I've tried loads with reloader 19, they don't fly well at all. We took apart a PPU FMJ which my gun loves and the powder was really fine, which suggested trying a faster burn. So far Varget has been the best, although you do lose some velocity with it to keep inside the pressure limit :rolleyes:

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I've just borrowed a gauge to measure the size of the chamber on my 6.5x55. With Speer 140grn softpoints it's measuring 3.170. I know I shoud back the bullet off the lands a little for pressure reasons, but how much? My Lee book says min OAL is 3.030 with Varget, but to have the bullet too far from the lands is bad? I can't for the life of me find where it says how much to back it off once measured, but I'm sure it did say somewhere when I read the whole book.

 

How do you guys go about it? I'm really stuck on this :rolleyes:

 

Are you measuring the OAL to the tip of the bullet or the ogive with a comparator?

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For an 85 grain bullet Varget is right up at the top as one of the best powders, so as the bullet gets lighter it is better. As the weight gets up, you need to slow the powder down because a fast powder pressures up faster than the bullet can accelerate. To get the best performance I need a slower powder. I'm thinking of getting a tub of reloader 22 to try.

 

Davo, I have no idea what these terms mean. I've got a gauge that is a threaded case. You put a bullet in it and push it into the chamber, then push the bullet to the lands with a rod which holds in place with a grub screw. You then pull it out, extract the bullet from the barrel and re-fit it to the case. Then you take the measurement from the base of the case to the tip of the bullet. :rolleyes:

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Hello i have an OAL gauge but have went back to a fire formed case with cut neck to shoulder on case.Dont want to confuse you but you will need a compareter to measure your correct seating depth with each diffrent bullet you use.

How your rifle likes it is a matter of try & test ie load 5 bullets of a load that works good for you & set it 10-30thou from lands & the next 5 80-110thou etc & test on paper.

I also helped a mate with his 243 & started load development by loading 3-5 batches of 5 bullets from min-max loads & tested them to see what worked best.I did this with great results & then resorted to playing/tweeking that load ie seating depth etc but groups went from 1.1/2" to 1/2" being the best & his smile was from ear to ear.

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Neil , once you get into this reloading lark you will find you have the odd bit of powder surplus mate.

Please dispose of it correctly and dont be falling into your old routine please. :good::D:lol:

 

 

I figured I'd just tip it on the floor and flick a match on it :good::lol:

 

My first loads worked out great. I made two batches 30 thou short of the lands and loaded them with 33 and 35grns of Varget. Both are shooting 5p groups at 50 yards, which is half the size Federal premium are giving me. I've now made some to the same length with Reloder19, 43 and 45grn charge. I wonder how they will go.

 

This reloading lark is great fun :lol:

 

EDIT......Forgot to add, I couldn't get v160

Edited by njc110381
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another vote for n160, we used 560? 540 cant remember which but was too slow, provided excellent flames but really didnt proove very accurate.

 

We also had issues getting the 6.5 using the 95grain nosler b/t to get even close the the lands. Also had similar issues with 108 grain? and 123 grain lapua scenar (those weights may be miles out, i just remember them being about 100 and about 120 grains)

 

However the 6.5 shot almost all of the above loads superbly.

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This might help:

 

As the amount of bullet jump decreases, pressures may increase. For this reason work up loads as you would with increasing powder charges. Start with the bullet 0.020" off the rifling for typical varmint calibers and 0.050" off for hunting rifles. Load three to five rounds at the suggested starting point and then vary the length both up and down by 0.010" while carefully watching for pressure signs. After you've found a length that seems to be working it might be worthwhile to try a change of 0.005" on either side

 

SF

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  • 3 weeks later...

With the very significant difference in bullet length in 6.5mm (from about 5/8" for an 80-grain up to about 1.3/8" for a 160 grain) I have found very little precision payback in careful seating depth unless loading 120 grain or heavier.

 

I'm getting excellent results with Vectan Tubal 3000 and 5000 in my 6.5x55. (All bullet weights).

 

With Vit at £65 per kilo at Tim Hannam and Vectan at £46 from Peter Lawman the savings are obvious.

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