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New Sierra 7mm bullet 183gr.

Posted: Tue Dec 15, 2015 1:43 am
by Frank Green
Don't know if this has been mentioned here or not. So if it has please forgive the duplicate post. I got my hands on some of the new Sierra 7mm 183gr. match bullets. I'll attach a couple of pictures as well. The bullets are 1.611" long (measured like 5 of them for a quick reference). The bullets are tips are closed up from Sierra. So you don't have to tip the bullets yourself. In the one picture a Berger 180VLD is pictured on the right hand side next to the Sierra. I'm going to load 20 rounds up and hopefully give them a quick test to see if they shoot thru my .284win. My barrel has a 1-9 twist. I'm not expecting them to shoot off hand. My twist calc comes in at 1-8.5 min. Sierra is recommending a 1-8 twist. I'll keep you posted.

Later, Frank
Bartlein Barrels

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Re: New Sierra 7mm bullet 183gr.

Posted: Tue Dec 15, 2015 5:44 am
by shooter mcreid
Thanks Frank, there is definitely a lot of interest in them over here. Would be great to hear how they go.

Re: New Sierra 7mm bullet 183gr.

Posted: Tue Dec 15, 2015 6:54 am
by williada
Frank ,this bullet looks like a long range bullet. Closed tip, smooth junction of the ogive with the body, and the thing I like best is the shallow long boat tail. All adds up to less turbulent drag in the latter part of the trajectory. Thanks for bring it to our attention.

Re: New Sierra 7mm bullet 183gr.

Posted: Tue Dec 15, 2015 8:40 am
by DenisA
It looks similar to a hybrid design in that the ogive / bearing surface isn't as pronounced as a VLD.

Re: New Sierra 7mm bullet 183gr.

Posted: Tue Dec 15, 2015 9:16 am
by Brad Y
Looks as though the throat might need lengthening a little for them as well? Maybe in the order of 0.300" freebore?

Re: New Sierra 7mm bullet 183gr.

Posted: Tue Dec 15, 2015 11:23 am
by ecomeat
No doubt we will get raped on price by the time they get to Australia. When I first built my F Class gun it was a 6x 47 Lapua and I was using 105 gr VLD's. When Stuart and Annie Elliott at BRT started importing Berger bullets, my price HALVED overnight. Those pricks at QGE were simply gouging us all to the maximum extent possible, charging $74 per hundred. BRT got their first shipment in and charged $37.
I am mentally scarred :mrgreen:

Re: New Sierra 7mm bullet 183gr.

Posted: Tue Dec 15, 2015 11:29 am
by Tim N
Hey Tony,
Careful you don't turn into a grumpy old man. :wink:
did you get the barrel vice?

Re: New Sierra 7mm bullet 183gr.

Posted: Tue Dec 15, 2015 11:57 am
by ecomeat
Tim N wrote:Hey Tony,
Careful you don't turn into a grumpy old man. :wink:
did you get the barrel vice?

Too late.....I am already there .
I sent you a "thank you" email the day Mike Samuels handed me the very fine Nugent barrel vice for cleaning spare barrels !.....the weekend after Canberra !!??

Re: New Sierra 7mm bullet 183gr.

Posted: Tue Dec 15, 2015 7:48 pm
by Norm
Got a box of 500 ready to test. :D

Bad news about the twist rate required though. Might have to save them until I get a new barrel. :(

Re: New Sierra 7mm bullet 183gr.

Posted: Wed Dec 16, 2015 2:55 am
by Frank Green
DenisA wrote:It looks similar to a hybrid design in that the ogive / bearing surface isn't as pronounced as a VLD.


My o.a.l. or if you want to call it where the bullet touches my rifling.....the dimension is virtually the same as the 180 VLD's in my rifle. The o.a.l. loaded length of the round ends up being longer as the bullets themselves are longer.

Later, Frank

Re: New Sierra 7mm bullet 183gr.

Posted: Wed Dec 16, 2015 2:57 am
by Frank Green
Norm wrote:Got a box of 500 ready to test. :D

Bad news about the twist rate required though. Might have to save them until I get a new barrel. :(


Norm, I'm curious about this as well. My barrel is a 1-9 twist and I've got 20 rounds loaded and ready to go. As soon as I can put a sided a couple of hours in the next few days I'm going to shoot them for a base line to see if they will shoot thru my rifle. I'll keep you posted.

My twist rate calc. tells me 1-8.5 min. but will give it a whirl!

Later, Frank

Re: New Sierra 7mm bullet 183gr.

Posted: Wed Dec 16, 2015 7:35 am
by Norm
My twist rate calculation for the area where I live, works out at 1 : 8.25
I will try a few in my 9 twist barrel but expect to be putting in an order with Craig for a Bartlein 1 : 8 twist in the new year.

Put a hummer aside for me Frank. :D

Re: New Sierra 7mm bullet 183gr.

Posted: Wed Dec 16, 2015 7:52 am
by Frank Green
Norm, The 1-8.52 (call it 1-8.5) was a min. calc. If it was my gun putting a new barrel on I would recommend a 1-8.25 or a 1-8 twist.

I've got guys over here shooting the new Berger 195's and most of the barrels we've made them have been 1-8.25 twist and shooting extremely well! No complaints. My twist calc on those came out to be 1-8.52 min. as well.

Humor ya! Will see! Probably will shoot it Thursday! Will keep you all posted!

Later, Frank

Re: New Sierra 7mm bullet 183gr.

Posted: Wed Dec 16, 2015 10:09 am
by plumbs7
I'm getting an sd factor of 1.25 for a 9 twist 1.40 puts it back in the green. We've had stories of 155 hybreds shooting very well with a 1:13 twist and I've heard 1:14 twist so who knows ??

Re: New Sierra 7mm bullet 183gr.

Posted: Wed Dec 16, 2015 7:53 pm
by willow
Looking forward to hearing some test results on these bullets, they sure are sleek looking.