270 load guidance

[Roboch270]

Hi folks

I am a novice reloader. Please can you give me some pointers on a load I am trying to develop.

I am using 52 gr N165 and Hornady Sst 270/.277 140gr Bt Interlock Bullet.

I made a batch of 10 and tried them at various ranges. I was amazed how much better they grouped compared to my factory ammo but I was surprised how much they dropped.

With 100 metres zero they dropped 19cm at 200 meters and 54cm at 300.

I don't have a chronograph so unsure of the muzzle velocity.

Any advice is welcome.

Many thanks, Bob

 

[Malxwal]

There's a wealth of information online as regards load development and safely finding the maximum powder charge in your individual rifle/brass/bullet/,powder combo.You also need to fully understand what constitutes indicators of excess chamber pressure.
Without looking, not sure where you are with regard to Viht load data, but it's notoriously conservative. As long as you are comfortable you fully understand pressure signs, you can proceed to increase powder charge in 0.3 grain increments.

 

[JTO]

When I had a .270, someone loaded some rounds for me with 140gr Nosler BTs and N160 powder. They appeared to have the same trajectory and the 130gr factory loads. I think it was a 24" barrel. N165 might be a bit slow, perhaps, especially through a short barrel.

 

[south-nofolk-stalker]

Don’t worry about the drop, just use them, if their kind on the carcass.

I shot a 270 for a very long time and personally never went over 2950fps which is very mediocre, as long as you know what they’re doing that’s all that matters

 

[Tim.243]

Hi folks

I am a novice reloader. Please can you give me some pointers on a load I am trying to develop.

I am using 52 gr N165 and Hornady Sst 270/.277 140gr Bt Interlock Bullet.

I made a batch of 10 and tried them at various ranges. I was amazed how much better they grouped compared to my factory ammo but I was surprised how much they dropped.

With 100 metres zero they dropped 19cm at 200 meters and 54cm at 300.

I don't have a chronograph so unsure of the muzzle velocity.

Any advice is welcome.

Many thanks, Bob

my 150's have 56 of n165 and do 2750 with no drop like that. @paul o' will chip in

 

[Edinburgh Rifles]

Stoke it up if you want better trajectory
52gr of N165 is likely producing 2-300fps less than optimal

N160/N560/RL22/RS70 is the go to list of powders
Charges in the region of 56gr is not unusual with some going closer to 60gr (work up obviously!)

I ran a “hind and roe” load at around 2850fps and a “big boy” load at 3150fps

Terminal effect was the same on smaller/lighter deer but drop was as you describe

 

[Roboch270]

Thank you everyone who has taken time to reply.

On one hand I am pleased to have a load that seems to group consistently allowing me to make adjustments at various ranges.

On the other I am keen to learn about reloading and so I will try to incrementally increase the charge.

The gentleman I bought the N165 from showed me examples of high pressure on rounds and explained the consequences. I will proceed with caution!

Thanks again

Bob

 

[Will the chippy]

Vihts data is quite conservative.
Here is hornadys data. Your right at the bottom end of things.
But I'd rather an accurate load than miss with a barn storming load.

 

[Roboch270]

Vihts data is quite conservative.
Here is hornadys data. Your right at the bottom end of things.
But I'd rather an accurate load than miss with a barn storming load.

Thanks very much for this. I was using the viht data as I couldn't work out how to access hornady data. I will work up and see how my gun likes it.

 

[takbok]

@Roboch270 I used to load 60gr Vihtavouri N165 with 150gr Sierra Gamekings in my 270 for about 2850-2900fps. I fired charges of 61 & 62gr safely when working up charges.

With the 140gr you should be able to work up to a fairly full case over 60gr. I expect that you should be able to get around 3000fps.

I find the Vihtavouri data fairly conservative. Work up gradually and keep an eye out for signs of excess pressure.

 

[Roboch270]

Hi folks

Forgive the schoolboy question but when I looked on the viht website I saw that the maximum load data for the Swift bullet (which from what I understand is comparable to the hornady one) I noted that the maximum charge was 55.4 grains. The hornady website suggests that this is in fact less than the maximum load permissible with this powder for their bullet. Is it best to work up to the load data from the hornady website? As I say, sorry for the daft question but I am new to this and want to avoid dangerous pressures.

 

[Dunwaters]

Thank you everyone who has taken time to reply.

On one hand I am pleased to have a load that seems to group consistently allowing me to make adjustments at various ranges.

On the other I am keen to learn about reloading and so I will try to incrementally increase the charge.

The gentleman I bought the N165 from showed me examples of high pressure on rounds and explained the consequences. I will proceed with caution!

Thanks again

Bob

You can tame the drop by zeroing about 4-5Cms high at 100M, do that and you should be able to hold dead on out to around 180M and still hit a 15Cms circle.

 

[paul o']

my 150's have 56 of n165 and do 2750 with no drop like that. @paul o' will chip in

As others have said more go go dust and there be good to go beyond your wildest dreams lol.
150 sgk seated at 3250 coal 56gr n165 24" sporter Rem barrel 2754 fps.
Must add I don't crimp my bolt action loaded rounds

 

[Foxyboy43]

As above the web is your friend BUT only respectable manufacturers’ tables should be used. This is Viht’s for N165 and 140 gns bullets:-

Viht does indeed have a reputation for erring on the low side of powder weights but as every rifle is different you should assume nothing! You already have a load which shoots accurately - BUT are there any pressure signs? If not you can work up your loads by 0.2/0.3 gns increments in small batches until you get the velocity you aspire to ALWAYS checking for pressure signs then go back to the previous lighter load.
Good luck!

 

[Dunwaters]

As above the web is your friend BUT only respectable manufacturers’ tables should be used. This is Viht’s for N165 and 140 gns bullets:-
View attachment 361872
Viht does indeed have a reputation for erring on the low side of powder weights but as every rifle is different you should assume nothing! You already have a load which shoots accurately - BUT are there any pressure signs? If not you can work up your loads by 0.2/0.3 gns increments in small batches until you get the velocity you aspire to ALWAYS checking for pressure signs then go back to the previous lighter load.
Good luck!

Compared to some older .270 loads modern loads run a bit light, Jack O Connor lists loads that run well above today’s recommended max velocity, 2960fps with 150gr bullets.
Not too shabby for a 99 year old cartridge.