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6.5 Creedmoor brass


Malxwal

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I don’t, many don’t. 

I use the Lapua 6.5 Creedmoor small primer brass to great effect in my AT - they don’t make LR primer brass so figure they must have chosen SR for a reason!

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Yes you need 1.5 mm decapping pin, spud 1967 does them, I also use Lapua SR brass, and you do have to increase the charge weight, I’m using Morom KVB 223M primers 44.2 grains of N160 139 Lapua scenars 2723 avg 3.9 Sd shooting 0.4 Moa

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Okay, thanks folks. Not sure if the owner, will buy factory then re-use brass, or just bite the bullet and buy brass. I would imagine I will be looking for dies very shortly either way, and to keep costs down, was looking at Lee dies. Would this pose an issue regarding de-priming pin, as I recall the pin is not replaceable, only the whole mandrel ?

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56 minutes ago, Malxwal said:

Okay, thanks folks. Not sure if the owner, will buy factory then re-use brass, or just bite the bullet and buy brass. I would imagine I will be looking for dies very shortly either way, and to keep costs down, was looking at Lee dies. Would this pose an issue regarding de-priming pin, as I recall the pin is not replaceable, only the whole mandrel ?

If you want to use Lee dies, it’s a fairly quick job to spin the Lee decapper in a drill and remove material from the pin with a file till you get a uniform 1.5mm.

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48 minutes ago, Ballistol said:

If you want to use Lee dies, it’s a fairly quick job to spin the Lee decapper in a drill and remove material from the pin with a file till you get a uniform 1.5mm.

Yes, and I can do a lot better than that; put them in the lathe and turn or polish them down. Why this didn't occur to me at time of writing God knows. Tendency for opening gob without engaging brain sometimes...

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4 hours ago, Malxwal said:

Yes, and I can do a lot better than that; put them in the lathe and turn or polish them down. Why this didn't occur to me at time of writing God knows. Tendency for opening gob without engaging brain sometimes...

Malxwal,

I have around 200 once and twice fired SRP lapua brass (all mixed up im afraid) that I will be putting in the for sale section soon.

If you want to try a small batch in your rifle before committing to buying 100 new PM me and I am sure we can sort something out 

 

Ed

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2 hours ago, biged85 said:

Malxwal,

I have around 200 once and twice fired SRP lapua brass (all mixed up im afraid) that I will be putting in the for sale section soon.

If you want to try a small batch in your rifle before committing to buying 100 new PM me and I am sure we can sort something out 

 

Ed

PM incoming Sir !

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There was initially limited choice of brass for 6.5CM when it first came out, with Hornady being the first (for obvious reasons) to supply it.  It was in LR form and soon gained a reputation for not lasting much more than 5 re-firings (less in some cases).   The main issue was that the head was deforming and primer pockets working loose with high chamber pressures that CM was capable of.  To combat this,  Lapua (and others) brought out SRP brass which lasted a lot better.

However, there's a trade off.  Whilst SRP brass will last longer due to having more meat on the head (therefore takes longer for proper pockets to come loose), the small primer also has less energy on ignition. This translates to lower MVs when you compare load for load with LRP brass.  Much lower.   In comparisons with fellow shooters, for a given load of 43.5gr RS62, LRP brass is delivering between 100 and 120fps more than SRP brass due to the primer differences.

The second issue is that of cost.  SRP brass costs almost twice what LRP brass does.

The main elephant now entering the room though is better LRP brass is available that lasts better than the original Hornady LRP brass, so the only real advantage is that SRP brass appears to offer more consistently lower SD/ES which is why it has become more popular with long range target shooters.  Once at 1000 yds, the terminal velocity differences of a 2700fps MV (SRP) and 2800FPSMV (LRP) with say a 139 Scenar become surprisingly marginal, so you can see perhaps why SRP brass has had it mostly its own way until recently.  However, I shall be moving to the cheaper option of LRP brass for the more economical loads and better MVs and should expect as long as charges aren't to hot to see 8 to 10 reloads.  As long as ES remains close to single digits, that'd be good enough for me.

Others I know who shoot 6.5CM are doing similar since we can't see any significant advantages of SRP any longer.

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I agree with VarmLR. I've been up and down powder charges with Lapua SRP trying to get an accurate, low/moderate chamber pressure with a "decent" velocity. I don't think i've helped myself by maybe buying a less than ideal powder. That being Viht N150.  I quickly found a great load for the 139 Scenar, and the TMK 130. But the 143 VLD-X was hard work. Although I have found a reasonable balance now. I think LRP brass would have made things a bit easier.

Just to add, while struggling to get a reasonable velocity with SRP, I tried the same load with LRP, (Murom KVB-7) and Hornady brass and instantly the velocity jumped very high indeed! Infact after 2 shots i stopped shooting due to high pressure signs, and silly barrel burning speed! 

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Well, I will likely be going with the SRP on offer to me, primarily to keep the costs for my pal down. The rifle will be mostly fed 120/123 stuff, that is all its owner requires of it (it's a deer rifle primarily, medium range gongs purely for fun second).

Hopefully we can the 120s up to around the 2950 mark (24" barrel).

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The brass will be fine but 2950 if using single base from a 24 inch barrel may be over-optimistic for SRP brass.  I was achieving about 2840 with reasonably hot (45.4gr) loads and RS62 in SRP brass using 123 scenars and an accuracy node (24 inch barrel) was at 44. 9gr/2800fps.  2950 seems unlikely (as well as unecessary?) unless pushing the bullet with a higher energy double base loaded very hot.

It would be more easily achievable using LRP brass if the velocity was a must.

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Thanks for that. it's all good info to pass on to its owner. For me it's the accuracy that comes first, and the difference in drops involved in maximum 300 yard shots , the lack of that 100-150fps for the sake of spot on accuracy is worth it.

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SRP brass is available at more sensible prices nowadays, Kranks have Starline SRP at £71.20/100 (and LRP at £58.40) .  It also has the standard size flash hole so no need for the smaller decapping pin.

I have 100 of the Starline SRP that have just had their 5th firing with no signs of any obvious problems, I've annealed them ready for their next outing.

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2 hours ago, Malxwal said:

Thanks for that. it's all good info to pass on to its owner. For me it's the accuracy that comes first, and the difference in drops involved in maximum 300 yard shots , the lack of that 100-150fps for the sake of spot on accuracy is worth it.

SRP will be fine and he'll get more reloads from it.  If moderately loaded, I'd expect at least 15 reloads if not more before primer pockets started becoming a bit loose.  Annealing every so often won't hurt either for ensuring consistent neck tension.

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I am looking forward to getting started with it, even though it's not my rifle. It's primarily a deer rifle, and the main reason for going down this route as for a wee step up in knock down over the 243. It was going to be 25-06, but just couldn't lay hands on a 24" barreled left hander (not within budget anyway), and when this particular rifle surfaced, he decided it would be worth a go.

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As a deer rifle, you may be better using LRP brass. The SRP variety struggles with some powders, but more to the point, may see significant velocity drops in very cold conditions or even hang/misfires.

The other potential downside with SRP in high-pressure cartridges is that the small primer is much more prone to severe extrusion back around the firing pin than the large variety. This can manifest itself as 'cratering' or in extreme cases 'blanking' where a disc of primer cup brass detaches and is blown back into the bolt.

This is a firing pin tip diameter + pin tip fit in the bolt-face issue. Some rifles are prone to it. (Mik Mak of Dolphin Gun Co. tells me he has done the firing pin reduction / bolt bushing job on over 30 AI rifles - they were fine with 308 Win or 260 Rem etc, but struggled with a rebarrel to 6.5X47mm Lapua and its small primer. I have an FN SPR Winchester 70 based tactical rifle that is hopeless with SR brass, so I've kept as a 260 as I'd only switch to Creedmoor if I could use the SRP variants - entirely for range use in my case.)

Note too, this will become a bit more of an issue over time. Peterson Cartridge is offering 243 Win, 260 Rem now in both varieties alongside Creedmoor and 308. We'll maybe see some confusion as these get here and are bought by those unaware of the differences and implications. 6.5 Grendel comes in various forms - at least three primer size / flash-hole diameter variations. I'm sure we're going to see more of these new versions of other cartridges too from Lapua, Peterson and some of the other young US case manafurers.

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Bushing the firing pin on an AI is not recommended, and not supported under warranty by the factory. As one customer has just found out, its also a very expensive repair.

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I'll have the SRP, and probably forty LRP Hornady cases, as my pal has ordered a couple of boxes of factory ammo. So, we'll be able to do some form of comparison between the two and make a decision on the way forward. The rifle is a T3 action, which I would think has formed the basis for many Creed rebarrel jobs by now ?

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23 hours ago, Laurie said:

As a deer rifle, you may be better using LRP brass. The SRP variety struggles with some powders, but more to the point, may see significant velocity drops in very cold conditions or even hang/misfires.

The other potential downside with SRP in high-pressure cartridges is that the small primer is much more prone to severe extrusion back around the firing pin than the large variety. This can manifest itself as 'cratering' or in extreme cases 'blanking' where a disc of primer cup brass detaches and is blown back into the bolt.

This is a firing pin tip diameter + pin tip fit in the bolt-face issue. Some rifles are prone to it. (Mik Mak of Dolphin Gun Co. tells me he has done the firing pin reduction / bolt bushing job on over 30 AI rifles - they were fine with 308 Win or 260 Rem etc, but struggled with a rebarrel to 6.5X47mm Lapua and its small primer. I have an FN SPR Winchester 70 based tactical rifle that is hopeless with SR brass, so I've kept as a 260 as I'd only switch to Creedmoor if I could use the SRP variants - entirely for range use in my case.)

Note too, this will become a bit more of an issue over time. Peterson Cartridge is offering 243 Win, 260 Rem now in both varieties alongside Creedmoor and 308. We'll maybe see some confusion as these get here and are bought by those unaware of the differences and implications. 6.5 Grendel comes in various forms - at least three primer size / flash-hole diameter variations. I'm sure we're going to see more of these new versions of other cartridges too from Lapua, Peterson and some of the other young US case manafurers.

I used my SRP brass with KVB-M primers throughout the winter Laurie including a few freezing cold days and with RS62 at any rate experienced no hang/misfires.  I also chrono'd velocities at 5, 12, 20 and 24 degrees and they were surprisingly tight wrt to differences at extremes (within 25fps) which points to RS62 being pretty stable. Others may have different experiences.  As a caveat I always keep my ammo box out of direct sunlight which makes quite a difference to case temperatures!

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2 hours ago, VarmLR said:

I used my SRP brass with KVB-M primers throughout the winter Laurie including a few freezing cold days and with RS62 at any rate experienced no hang/misfires.

Good to know. The 'problem' with SRP brass and 40gn + charges is one of potential powder sensitivity. My experience is with the slightly larger case and charge weight 308 Win 'Palma', another two to six grains powder. In one case (Hodgdon CFE223 'spherical') I got 48 hangfires and two complete misfires at normal UK spring temperatures from 50 rounds; in others (Viht N140 particularly) performance began to be affected below around 3 or 4-deg C. Yet while N140 went to pieces and CFE apparently doesn't work at all in any temperature, N150 works right down to freezing (at least) and H414 'spherical' (made in the same factory as CFE) actually gave higher MVs and smaller ES than in Lapua LRP brass at just above freezing.

One of the American 243 Win long-range shooters assured me on another forum that Peterson Cartridge Co. SRP 243 brass was hopeless with his favourite compressed load of coarse-grain / slow burning Hodgdon H1000 in US summer temperatures - 200 fps MV reduction and huge ES values.

So, whilst the range user is pretty safe with most primer / powder combinations in the small primer / small flash-hole combination, there is a chance even in our climate that the sporting user could be caught out on particularly cold days and finding your rifle shoots several inches low at a couple of hundred yards range after a long Scottish Highland glen stalk on a red deer isn't fun for either stalker or deer I'd imagine.

Just to complicate matters, it seems the small 1.5mm flash-hole is as much a cause of these behaviours as the primer size and brisance, maybe even more so, and it seems some of the new US made SRP versions have stuck to the large (2mm) flash-hole. Starline SRP brass is in this form inlcuding its Creedmoor it seems.

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