7 mag and Speer 145 hot cor

acj7382

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Can't find much loading information on these. Seems from Internet it doesn't like speeds much more than 2800 fps. I've used imr 4831 pretty much exclusively for bullet weights fro 140 to 163 with very good results but not this bullet. I have about 100 on hand and would like to find some decent loads that will compare with my other bullets at sub moa. I bought these for reviews of good kills within the 100-200 yard range. I don't have a Speer manual and other three don't show a 145 bullet load so I split the difference and drooped a few grains on the 140 and tested up. Maybe I'm over driving it at 2980 fps but groups with ladder test are at best average of 1.8. Hunting I'm sure this is satisfactory it has to be a way to tighten these up.
 
The 140 grain data will do for a 145. Five grains won't make any difference. You do not need bullet specific data.
Hodgdon's 140 grain data starts at 2880 FPS, so the Internet, as usual, is confused.
A ladder test tells you very little. Only tells you the POI compared to other loads. Doesn't tell you anything about the accuracy of a particular load out of your rifle.
 
From Speer's Reloading Manual (145 gr., 7mm Remington Magnum):

COAL (Bullet 1629): 3.280”
IMR4831, Mag primer

Max: 63.0gr.

Start load is reduced about 6%.
 
I would recommend you look at Alliants website.

Pretty much all they list is Speer.

Of course Vista Outdoors owns both.
 
I have a sketchy recollection about this bullet.Its from probably 20 years ago.It may well be outdated.Products get improved.

I was looking at(what may have been) this bullet for my 7mm Rem Mag.It was a nice weight with a good BC.

There was a note in the load manual that this bullet was designed for the 7x57.
It said the bullet base/jacket thickness was not up to maximum 7mm Rem loads. They imposed a lower max for that reason.
 
I have a sketchy recollection about this bullet.Its from probably 20 years ago.It may well be outdated

I bought some not long ago, the box is different but bullets seem the same. Speer's site still lists them, #1628 for the boat tails, #1629 for the flat base.
 
Mine are flat base. I think I got them from Midway last year. Maybe if I can't get good groups out of the magnum I might try in 7-08. Seems like I had some 165 flat base Sierras that done good in the magnum with Reloader 22. Not a very temperature stable powder though. At least my results from fall loads to dead cold months.
 
acj, H-4831 is a Hogdon Extreme powder (temp stable).

I can't say it is the last word best powder for your 165 gr Sierra,but its one of the better powders.

Old Scot,I meant my memory might be outdated!

Sometimes we shooters have an experience with a product decades ago and then forever,30 years later,we cling to the idea that "X" primer or "Y" brass or "Z" bullets are forever what we experienced.

I try to recognize successful manufacturers actually try to discover and correct shortcomings in order to survive.

But still,that bullet may be made for the 7x57,and 7-08.Its a niche.

Not all 7mm bullets need to be made for magnums.
 
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HiBC - I agree, Speer's Hot Cor bullets is their basic "affordable" cup and core offering.

The Grand Slam bullets are their pricier line, and its construction may be better suited to magnum level velocities.

That said, it's not impossible to download a magnum somewhat and still get decent accuracy. I have a nice moderate load for my 338 Win Mag using basic cup and core 200 grain bullets. I've used it on our little central Texas whitetails and it works nicely.
 
I used 145 Speers for a long time in the 70s-80s. I was pushing them to 3160 with a "then Max" of old H4831. Speer was correct in their advice to keep impact velocities below 3000fps because it was a bomb. DRT, but a huge mess, including a complete evisceration on a quartering 160 yard shot. Speer 14 lists IMR 4831 at 59-63gr. Only difficulty with the 3 7s I've owned and several I've loaded for is they are the most accurate at Max or close. I've been using 154 Interbonds and 150 Partitions the past few years.
 
I’ve got some H4831 sc but not just H4831. Slow powder for 260 I load for but H4831sc makes 1 hole groups. I’ve got some 160 and 175 grand slams I bought pulled from somewhere. My old adl didn’t do too bad with them but I haven’t tried them in the Sako. 1-9.5 twist I think. Accuracy bullet for the Sako and Sendero is about 61-62 grains of imr 4831 using federal brass and 150 grain combined technology silverip. Rem 9.5 magnum primers. Average 1/2 inch all day. Maybe some H4350 with the 145 hc in 7-08. Worth trying.
 
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acj: I should have included the "sc" with my 4831 suggestion.Per Hogdon,data is interchangeable.
The H4831 sc meters better,less crunching. I don't know of any advantage to long stick 4831
I only stock H4831sc.
If you look at Nosler data for 150 gr bullets,IMR4350 is no slouch.

I'm not sure how the temp sensitivity stacks up for the IMR 4350.
The Hogdon extreme series is among the best for temp stability.

For 160 gr + bullets in the 7mm Rem,I have had good results with H-1000,also.
FWIW,its a 26 in bbl.
Once again,my comment on the 145 gr Speer is sketchy.Its based on a memory of reading something decades ago when I was interested in loading the bullet.As I recall,Speer suggested the bullet jacket was quite thin at the base,and it distorted under the pressures of full power 7mm Rem loads.This was an old green cover load manual,maybe 80's vintage.
Today,I'd rate the relevance and cred of my comment as "mediocre"

But it might be true.
 
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Hibc I'm sure glad you brought up the H1000. I've got a full lb never been opened. Mines a 24 inch and one in a 26 inch. That may just work with the 160 and up. Also been trying for Hornady 163 grain eldx. Never thought to use the H1000.
 
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